The purposes of this research were to study and compare the factors affecting voters decision making in mayor election in Trat Town Municipality Area, Muang District, Trat Province. The research populations determined by the Yamane’s sampling method were the 7,446 qualified voters in the area of Trat Municipality. The sample group was the 379 people. The research instrument was a questionnaire enquiring about the factors affecting voters’ decision making in mayor election in Trat Town Municipality Area, Muang District, Trat Province. The descriptive statistics were frequency, percentage, mean, standard deviation, t-test, one way analysis of variance and the Scheffe’ s test.