In bold, the official abbreviations
- Iamonico, D (Iamonico) Duilio Iamonico (1976– )
- Iamwiriyakul, P (Iamwir.) Prapanth Iamwiriyakul
- Iatroú, G (Iatroú) Gregoris Iatroú (1949– )
- Ibáñez, C Carlos Ibáñez
- Ibáñez, R Roberto Ibáñez
- Ibañez-Bernal, S Sergio Ibañez-Bernal
- Ibarra-Vidal, H (Ibarra-Vidal) Héctor Ibarra-Vidal
- Ibiza, L (Lázaro Ibiza) Lázaro Ibiza (1858–1921)
- Ibn Tattou, M (Ibn Tattou) Mohammed Ibn Tattou
- Ichiyanagi, T Takashi Ichiyanagi
- Ickert-Bond, SM (Ickert-Bond) Stefanie M. Ickert-Bond (1966–)
- Icochea, J Javier Icochea
- Ida, R (Ida) Reijiro Ida (fl. 1969)
- Idris, AG Idris Abd. Ghani (1957–)
- Ietswaart, JH (Ietsw.) Jan Hendrik Ietswaart (1940–2004)
- Igarashi, S (Igarashi) Suguru Igarashi
- Iglesias, CG (Iglesias) Carlos G. Iglesias
- Iglikowska, A Anna Iglikowska
- Ignatov, MS (Ignatov) Mikhail Stanislavovich Ignatov (1956–)
- Ignatova, EA (Ignatova) Elena Anatolievna Ignatova (1956–)
- Ignatyev, NN (Ignatyev) Nikolay N. Ignatyev
- Igo, H Hisayoshi Igo
- Ihara, Y Yoh Ihara
- Iharlegui, L (Iharl.) Laura Iharlegui (1943–)
- Ihering, H Hermann von Ihering (1850–1930)
- Ihering, R Rudolph von Ihering (1883–1939)
- Ihle, S (S. Ihle) Siegfried Ihle
- Ihlen, PG (Ihlen) Per Gerhard Ihlen
- Ihlenfeldt, HD (Ihlenf.) Hans-Dieter Ihlenfeldt (1932– )
- Iihara, H Hirotoshi Iihara
- Iinuma, Y (Iinuma) Yokusai Iinuma (1782–1865)
- Iizuka, H Hiroshi Iizuka
- Ijima, I Isao Ijima (1861–1921)
- Ikeda, H Haruo Ikeda
- Ikeda, H Hiroyoshi Ikeda
- Ikeda, H Hyozi Ikeda
- Ikeda, Y Yoshinori Ikeda
- Ikeya, N Noriyuki Ikeya
- Ikonnikov-Galitzky, NP (Ikonn.-Gal.) Nikolai Petrovic Ikonnikov-Galitzky (1892–1942)
- Ilango, K (Ilango) K.Ilango
- Ilardi, V (Ilardi) Vincenzo Ilardi
- Ilarslan, R (Ilarslan) Reşit İlarslan (1954– )
- İlçim, A (İlçim) Ahmet İlçim (fl. 2006)
- Iles, TD Thomas Derrick Iles
- İlhan, V (İlhan) Veli İlhan (fl. 2014)
- Iliff, J (Iliff) James Iliff (1923– )
- Iliffe, TM Thomas M. Iliffe (1948– )
- Iliopoulou-Georgudaki, J Joan Iliopoulou-Georgudaki
- Iljin, MM (Iljin) Modest Mikhailovich Iljin (1889–1967)
- Iljina, AP (A.P.Iljina) Agnija Petrovna Iljina (1904–1998)
- Iljina, EV (E.V.Iljina) Elena Vyacheslavovna Iljina (1960–)
- Iljina, LB (L.B.Iljina) Lyubov Borisovna Iljina (1926–2013)
- Iljina, LP (L.P.Iljina) Lyudmila Petrovna Iljina (1923–2019)
- Iljina, VI (Iljina) Vera Ivanovna Iljina (1930–2018)
- Ilkiu-Borges, AL (Ilk.-Borg.) Anna Luiza Ilkiu-Borges (1972– )
- Illies, J Joachim Illies (1925–1982)
- Illiger, JKW Johann Karl Wilhelm Illiger (1775–1813)
- Ilnickaja, NM N. M. Ilnickaja
- Ilse, H Hugo Ilse (1835–1900)
- Iltis, H (H.Iltis) Hugo Iltis (1882–1952)
- Iltis, HH (Iltis) Hugh Hellmut Iltis (1925–2016)
- Imadate, G Gentaro Imadate
- Imaizumi, Y Yoshinori Imaizumi
- Imamura, T Taiji Imamura
- Imhoff, L Ludwig Imhoff (1801–1868)
- Imlay, G George Imlay (1754– )
- Imlay, JB (J.B.Imlay) Joan B. Imlay
- Imlay, RW Ralph Willard Imlay (1908-1989)
- Imms, AD Augustus Daniel Imms (1880–1949)
- Imshaug, HA (Imshaug) Henry Andrew Imshaug (1925– )
- Imura, Y Yûki Imura
- Inada, S (Inada) Satoshi Inada
- Inayoshi, Y (Inayoshi) Yutaka Inayoshi
- İnceer, H (İnceer) Hüseyin İnceer (fl. 2008)
- Indrawan, M Mochamad Indrawan
- Ineich, I Ivan Ineich (1957– )
- Infante, F (Infante) Francisco Infante García-Pantaleón fl. 2003
- Infante, M (M.Infante) Marta Infante (1964– )
- Infantes, JG (Infantes) Juana G. Infantes Vera (1907–1974)
- Inganäs, E Elisabeth Inganäs
- Inger, RF Robert Frederick Inger (1920–2019)
- Ingleby, K Kevin Ingleby
- Ingram, A A. Ingram
- Ingram, C Collingwood Ingram (1880–1981)
- Ingram, JW (J.W.Ingram) John William Ingram (1924– )
- Ingrisch, S (Ingrisch) Sigfrid Ingrisch
- Innes, WT William T. Innes (1874–1969)
- Inomata, T (Inomata) Toshio Inomata
- Inoue, H (Inoue) Hiroshi Inoue (bryo.) (1932–1989)
- Inoue, H Hiroshi Inoue (ent.) (1917–2008)
- Inoue, M (Mas. Inoue) Masakane Inoue (1949– )
- Inoue, M (May. Inoue) Mayumi Inoue (1918–199x)
- Insom, E Emilio Insom
- Intes, A Andre Intes
- Inumaru, S (Inumaru) Sunao Inumaru (1899–1988)
- Ionescu, MA Mihal A. Ionescu
- Ippolitova, A Alexandra Ippolitova
- Iqbal, M Muhammad Iqbal
- Iranshahr, M (Iranshahr) Mousa Iranshahr (1923– )
- Iredale, T Tom Iredale (1880–1972)
- Ireland, RR Robert Root Ireland (1932– )
- Irie, T Teruo Irie
- Irish, J John Irish (1958–)
- Irizuki, T Toshiaki Irizuki
- Irmisch, JFT Johann Friedrich Thilo Irmisch
- Irmler, U (Irmler) Ulrich Irmler
- Irmscher, E (Irmsch.) Edgar Irmscher (1887–1968)
- Irschick, DJ Duncan J. Irschick
- Irvine, AK (A.K.Irvine) Anthony Kyle Irvine (1937– )
- Irvine, FR (F.Irvine) Frederick Robert Irvine (1898–1962)
- Irvine, LM (L.M.Irvine) Linda Mary Irvine (1928– )
- Irving, RS (R.S.Irving) Robert Stewart Irving (1942– )
- Irving, W (W.Irving) Walter Irving (1867–1934)
- Irwin, HS (H.S.Irwin) Howard Samuel Irwin (1928– )
- Irwin, ME Michael Edward Irwin (1940– )
- Irwin, MS Michael Stuart Irwin
- Isbrand, S (Isbrand) Sofie Isbrand
- Isbrücker, IJH Isaac J.H. Isbrücker
- Isely, D (Isely) Duane Isely (1918–2000)
- Isert, PE Paul Erdmann Isert (1756–1789)
- Ishida, H (H. Ishida) Hiroshi Ishida (1919–?)
- Ishida, K (K.Ishida) Ken-ichiro Ishida (1966–)
- Ishida, M (M.Ishida) Masato Ishida (1877–1940)
- Ishida, N (N.Ishida) Noriko Ishida (19..–)
- Ishida, S (S.Ishida) Shiro Ishida (1930–)
- Ishida, Y (Y.Ishida) Yoshiaki Ishida (1948–)
- Ishihara, H Hajime Ishihara
- Ishii, T Tohru Ishii
- Ishikawa, C Chiyomatsu Ishikawa (1861–1935)
- Ishikawa, T (T.Ishikawa) Tadashi Ishikawa
- Ishizaki, K Kunihiro Ishizaki
- Ishizuka, K (Ishizuka) Katsumi Ishizuka
- Ising, EH (Ising) Ernest Horace Ising (1884–1973)
- Iskandar, DT Djoko T. Iskandar
- Isler, ML Morton L. Isler
- Isler, PR Phyllis R. Isler
- Ismail, G (G.Ismail) Ghazally Ismail
- Isoviita, P (Isov.) Pekka Isoviita (1931–2016)
- Israelsson, O Olle Israelsson
- Issel, A Arturo Issel (1842–1922)
- Issiki, S Syuti Issiki (1892– )
- Itämies, J (Itämies) Juhani Itämies
- Ito, G Gen Ito
- Ito, H (H.Itô) Hiroshi Itô (1909–2006)
- Ito, M (M.Ito) Motomi Ito
- Ito, T (T.Itô) Tokutarô Itô (1868–1941)
- Itoh, T Takashi Itoh
- Ittenbach, S (Ittenb.) Stephan Ittenbach (1964– )
- Iturra, P Patricia Iturra
- Iturriaga de Capiello, T (Iturr.) Teresa Iturriaga de Capiello
- Itzerott, H (Itzerott) Heinz Itzerott (1912–1983)
- Itzigsohn, EFH Ernst Friedrich Hermann Itzigsohn (1814–1879)
- Ivanenko, VN Viatcheslav N. Ivanenko
- Ivanitskaya, E Elena Ivanitskaya
- Ivanov, AN (A.N.Ivanov) Anatolij Nikolaevich Ivanov (1910–1991)
- Ivanov, AO (A.O.Ivanov) Alexander Olegovich Ivanov (1959–)
- Ivanov, AP (A.P.Ivanov) Alexander Pavlovich Ivanov (1903–1982)
- Ivanov, AP (Al.P.Ivanov) Alexey Pavlovich Ivanov (1865–1933)
- Ivanov, DL Dimitri Lumbergovitsch Ivanov (1955– )
- Ivanov, GI (G.I.Ivanov) Gennadii Ivanovich Ivanov (1948–)
- Ivanov, KS (K.S.Ivanov) Kirill Svyatoslavovich Ivanov (1955–)
- Ivanov, NR (N.R.Ivanov) Nikolai Rodionovich Ivanov (1902–1978)
- Ivanov, VD Vladimir Dmitrievich Ivanov
- Ivanov, VK (V.K.Ivanov) Vitalij Konstantinovich Ivanov (1937–)
- Ivanova, EA (E.Al.Ivanova) Elena Alexeevna Ivanova (1901–2005)
- Ivanova, EA (E.A.Ivanova) Evgenija Anempodistovna Ivanova (1912–?)
- Ivanova, EF (E.F.Ivanova) Ekaterina Filippovna Ivanova (1925–1985)
- Ivanova, KV (K.V.Ivanova) Klavdia Vasilievna Ivanova (1903– )
- Ivanova, VA Valentina Alekseevna Ivanova
- Ivantsoff, W Walter Ivantsoff
- Iversen, J (Iversen) Johannes Iversen (1904–1971)
- Iverson, JB John B. Iverson
- Ives, JC (Ives) Joseph Christmas Ives (1828–1868)
- Ives, JE James Edmund Ives
- Ivie, MA Michael A. Ivie
- Ivie, W Wilton Ivie (1907– )
- Ivinskis, P (Ivinskis) Povilas Ivinskis
- Iwamoto, Y (Iwamoto) Yoshiya Iwamoto
- Iwanoff, KS (K.S.Iwanoff) Konstantin Semenovich Iwanoff (1879–1906)
- Iwanoff, LA (Iwanoff) Leonid Alexandrovich Iwanoff (1871–1962)
- Iwarsson, M Mattias Iwarsson (1948– )
- Iwasaki, H (Iwasaki) Hiroaki Iwasaki
- Iwatsuki, K (K.Iwats.) Kunio Iwatsuki (1934– )
- Iwatsuki, Y Yukio Iwatsuki
- Iwatsuki, Z (Z.Iwats.) Zennosuke Iwatsuki (1929–2015)
- Izard, D Daniel Izard
- Izawa, K (Izawa) Kunihiko Izawa
- Izecksohn, E Eugênio Izecksohn (1932–2013)
- Izmailova, MV M.V. Izmailova
