A study of environmental marketing factors affecting student behavior regarding trips to places of amusement in Mueng Mahasarakham. The sample group used in this research were university students in Mueng Mahasarakham from eight institutes. Five hundred students were chosen for the sample group. The instrument used in this research was a questionnaire. Statistics used were descriptive, composing frequency, arithmetic mean percent and standard deviation. Test statistics were t-test and f-test. Preferred places of amusement were firstly restaurants having music (48.80%). The next most popular place of amusement was Tawandang (35.00%). The frequency of visits was once or twice per month (52.40%). A large number from the dormitory sought amusement (52.60%). Optimum days for seeking entertainment were Friday through Sunday (69.60%), and time was 11.01 p.m. – 01.00 a.m. (54.40%). Average costs per trip exceeded 500 baht (31.40%) and the length of each outing was 2-4 hours (54.00%). Activities at places of amusement included drinking alcohol (36.00%), and they preferred to be with their friends (80.80%). About 54.40% were given money by their parents, and those learning of places of amusement from friends accounted for 64.60%. Some went just for fun (39.60%), and if they needed but didn’t have money, they borrowed from friends (65.40%).The environmental marketing factors affecting student behavior in the sample group regarding going to places of amusement was firstly that they selected less expensive places selling discount beverages (X=4.15). The second choice was a show or concert to see a famous star (X=4.07) and arranged the group numbers from many to few, depending on who was interested (X=3.92). Other factors were politics (X=3.83), technology (X=3.82), economics (X=3.64), and on the social middle class (X=3.09). Choice of which amusement place to go to differed between the genders; opinions also differed based on income per month, education, if they were working farmers and the amount of family income at the significance level of 0.05. However, working mothers did not differ in opinion.