This study aimed to determine the effect of the principal's leadership behavior and work environment on teacher teaching satisfaction at Teladan Private Senior High School Pematang Siantar. The problems discussed in this study are the principal's leadership behavior and the work environment that affect teacher teaching satisfaction at Teladan Private High School Pematang Siantar. This study uses a quantitative approach, namely the measurement of quantitative data and objective statistics through scientific calculations derived from the sample/population who were asked to answer a number of questions about the survey to determine the frequency and percentage of responses. According to the results of hypothesis testing, it was found that the leadership and work environment together influences the teaching satisfaction of Teladan Private Senior High School teachers. Based on the results of data processing, it is stated that Leadership (X1) has increased by 1%, so teacher job satisfaction (Y) will increase by 0.284, and work environment (X2) has increased by 1%, teaching job satisfaction (Y) will increase by 0.198.