The purpose of this study is to develop an understanding of the causes and effects of gender discrimination in the Thai workplace. The research focuses on gender differences related to recruitment, occupational segregation, compensation, pay raises, promotion opportunities, fringe benefits, and personnel policies and practices. Three hundred employees and ten supervisors of "Grarui and So Co., Ltd. participated in the study. Also, personnel policies and regulations were reviewed and evaluated. The findings showed female workers were more satisfied with fringe benefits and the practices of their supervisors, than were their male counterparts. Moreover, male workers perceived that their female coworkers were treated better by supervisors, especially in regard to compensation, pay raises and promotions. Traditional Thai social value and culture may be at the root of these unexpected findings / Master of Urban and Regional Planning