The problem occurred in Alfamart Damar, Semarang is the decrease in sales using a Ponta card. The purpose of this research is to determine and analyze the influence of member card (MC) on shopping activity (AB) at Alfamart Damar, Semarang. Collecting data methods used in this research were done through observation, interview, literature review and questionnaire. The questionnaire used in this research was semantic defferensial with 10 point of scale and the sampling technique used was purposive sampling as many as 90 samples. The analyzing data instruments used were validity testing, reliability testing, and normality testing. While the analyzing data techniques used were correlation analysis, coefficient of determination, t-test, and simple linear regression. Based on the calculations using SPSS version 17, the results of this research showed that the regression equation AB = 8,250 + 0,507MC. Moreover, the t-test had significance result lower than significance level 0f 0,05. So, it could be concluded that there was significant influence among independent variable – member card (MC) toward dependent variable – shopping activity (AB). The result of this study showed that coefficient of determination in R Square was 0.603, meaning that 60.3% of shopping activity could be explained by independent variable in this study that was member card. The rest 39.7% could be explained by other variables outside the model of this study.