This research was carried out with the objective of studying the methodology of standard germination test of cotton seeds mechanically delinted. Three seeds lots, cultivar IAC 20, were used. In order to improve standard germination test six combinations of temperatures and periods of evaluation (25°C/3 days; 25°C/4 days; 30°C/3 days; 30°C/4 days; 20-30°C/4 days and 20°C/5 days, without light) and three substrates (rolled paper towels, rolled cotton cloth and between sand) were compared. Replications of 50 or 25 seeds were used. Results showed that the most favorable temperature was 25°C with the first count at the third day after sowing. Cotton cloth was the most favorable substratum, when wetted in the proportion 2.5:1 (quantity of water: weight of cotton cloth), and the sand substratum was more favorable than paper towel.