The objectives of this study are to study the factors influencing to the decision to study nursing assistant program, and to analyze the personal cost for investment in this program in Chiang mai by 142 people. We divide into 2 parts such as the nursing assistant program students in Chiang mai University 103 people and in Payap University 39 people. The tool for research is questionnaire, and we analyze with descriptive statistics such as frequency, percentage, medium, maximum, and minimum. The found result is the most students are women. The average age is 26 years old, Their address is in Chiang mai, and they live in rented house, and dormitory. The average grade is in 2.01-2.50. Their parents are agriculturists and farmers. The average family income is 18,082 Baht, and the average income for the students is 4,258 Baht. Most students are not supported scholarship, and do not loan for education. The factors most influencing is personals, products, and information respectively. By the way, the personal costs of studying are the nursing assistant program (course 1year) of Chiang mai University which is 177,250.38 Baht- direct cost is 101,187.35 Baht per person in a course, indirect cost is 76,063.03 Baht per person in a course. Payap University, the cost is 174,856.29 Baht- direct cost is 98,838.82 Baht per person in a course and indirect cost is 76,017.47 Baht per person in a course. Because of high costs, the universities should provide scholarship in order to make the opportunity to them.