| Last Name | First Name | Year Sort descending | City | Section/Speaker Type |
|---|---|---|---|---|
| Ikawa | Mitsuru | 1990 | Kyoto | Partial Differential Equations |
| Ilyashenko | Ju. S. | 1990 | Kyoto | Ordinary Differential Equations & Dynamical Systems |
| Ivanov | Alexander A. | 1990 | Kyoto | Combinatorics |
| Jimbo | Michio | 1990 | Kyoto | Mathematical Physics |
| Jones | Lowell E. | 1990 | Kyoto | Topology |
| Jones | Vaughan F. R. | 1990 | Kyoto | Plenary/Prize winner |
| Kahan | William M. | 1990 | Kyoto | Computational Methods |
| Karzanov | Alexander V. | 1990 | Kyoto | Computational Methods |
| Kashiwara | Masaki | 1990 | Kyoto | Lie Groups & Representation |
| Kato | Kazuya | 1990 | Kyoto | Number Theory |
| Kawamata | Yujiro | 1990 | Kyoto | Algebraic Geometry |
| Kemer | Alexander R. | 1990 | Kyoto | Algebra |
| Kollár | János | 1990 | Kyoto | Algebraic Geometry |
| Kolyvagin | Victor Alecsandrovich | 1990 | Kyoto | Number Theory |
| Kotani | Shinichi | 1990 | Kyoto | Probability & Mathematical Statistics |
| Krasny | Robert | 1990 | Kyoto | Computational Methods |
| Krichever | Igor | 1990 | Kyoto | Mathematical Physics |
| Kronheimer | Peter B. | 1990 | Kyoto | Geometry |
| Kupiainen | Antti | 1990 | Kyoto | Mathematical Physics |
| Kusuoka | Shigeo | 1990 | Kyoto | Probability & Mathematical Statistics |
| Laumon | Gérard | 1990 | Kyoto | Number Theory |
| Lazarsfeld | Robert K. | 1990 | Kyoto | Algebraic Geometry |
| Le Cam | Lucien M. | 1990 | Kyoto | Probability & Mathematical Statistics |
| Lebeau | Gilles | 1990 | Kyoto | Partial Differential Equations |
| Lin | Fang Hua | 1990 | Kyoto | Partial Differential Equations |