Seeds of tropical maize genotypes were germinated at constant temperatures, ranging from 5°C to 45°C, in order to determine the most favorable temperature for germination. Analysis were performed according to the standard germination and speed of germination tests. Varieties BR 106 and BR 451, the double hybrid BR 201 and populations CMS 14 and CMS 54 showed optimal germination between 15°C and 35°C. population CMS and variety BR 126 germinated better between 20°C and 35°C, and population CMS 28 btween 10°C and 35°C. AlI genotypes had highest speed of germination at 35°C and no germination was recorded at 5°C and 45°c, Population CMS 28 may be a good gene source for tolerance to temperature as low as 10°C, and variety BR 451 to temperature as high as 40°C.