This study aims to examine the influence of independent variables perception of ease and usefulness, user satisfaction and training on the dependent variable of user performance. Objects in this research is minimarket Indomaret and Alfamart which exist in Sleman regency. While the subject in this study is all employees who interact directly using computer-based SIA software. The sample in this study amounted to 100 respondents selected based on purposive sampling method. The analysis used in this research is multiple linear regression analysis with SPSS 21.0. The results of the data in this study stated that the perception of ease and usefulness significantly influence the performance of SIA users, user satisfaction has no significant effect on the performance of SIA users, and user training significantly influence the performance of SIA users.