| Last Name Sort descending | First Name | Year | City | Section/Speaker Type |
|---|---|---|---|---|
| Claxton-Fidler | T. | 1908 | Rome | Various Applications of Mathematics |
| Clemens | C. H. | 1974 | Vancouver | Algebraic Geometry |
| Clemens | H. | 1986 | Berkeley | Algebraic Geometry |
| Clifford | A. H. | 1950 | Cambridge (USA) | |
| Clifford | A. H. | 1974 | Vancouver | Algebra |
| Clozel | L. | 1986 | Berkeley | Lie Groups and Representations |
| Coates | J. | 1978 | Helsinki | Number Theory |
| Coats | R.H. | 1924 | Toronto | Statistics, Actuarial Science, Economics |
| Coble | A.B. | 1924 | Toronto | Geometry |
| Cockburn | Bernardo | 2010 | Hyderabad | Numerical Analysis and Scientific Computing |
| Cogdell | J. W. | 2002 | Beijing | Number Theory |
| Cohen | Albert | 2002 | Beijing | Numerical Analysis & Scientific Computing |
| Cohen | F. R. | 1983 | Warszawa | Topology |
| Cohen | H. | 2002 | Beijing | Number Theory |
| Cohen | P. J. | 1962 | Stockholm | Analysis |
| Cohen | P. J. | 1966 | Moskva | 1/2 hr. report/Prize winner |
| Cohen | R. L. | 1983 | Warszawa | Topology |
| Cohn | Henry | 2010 | Hyderabad | Combinatorics |
| Cohn | P. M. | 1970 | Nice | Algebra |
| Cohn-Vossen | S. | 1928 | Bologna | Geometry |
| Coïalowitsch | B.M. | 1924 | Toronto | Algebra, Theory of Numbers, Analysis |
| Coifman | Ronald | 2018 | Rio de Janeiro | Plenary |
| Coifman | Ronald R. | 1990 | Kyoto | Real & Complex Analysis |
| Coker | E.G. | 1924 | Toronto | Engineering |
| Colding | Tobias H. | 1998 | Berlin | Differential Geometry and Global Analysis |