We have measured the specific heat C-p on sputtered amorphous Mn100-xCex alloys for 25 less than or equal to x less than or equal to 79 from 4.2 to 300 K using a light-chopped AC method. The C-p/T follows gamma + AT(2) law below 15 K in each Ce concentration. The gamma value increases systematically as a function of x and reaches 0.124 J/mol K-2 for x = 79, suggesting formation of a dense-Kondo and/or heavy-fermion state at low temperature for the Ce-rich side. Large magnetic contribution in C, has been observed at higher temperature, suggesting existence of large itinerant spin fluctuations. (C) 2003 Elsevier B.V. All rights reserved.