This research aims to study consumer behavior. Vitamin supplement in Bangkok. By means of two methods of quantitative research. The samples used in the research is that consumers total of 400 people in the statistics. Data analysis were frequency, percentage, mean, standard deviation. Chi-squared test (Chi - square), the coefficient of relative simple algorithm of Pearson. The qualitative research The observation is not involved. (Non-participation observation) and analyzed using synthetic material (Synthesis).