This study tries to determine what factors cause consumers’ impulse buying. This study uses 4 independent variables, that are positive emotions (X1), shopping environment response(X2), interaction between customers and sales person (X3), hedonic shopping value (X4), and impulse buying as the dependent variable (Y). After doing a literature review, and preparation of the hypothesis, the data were collected through a questionnaire distributed to 100 people of Alfamart shoppers in Banyumanik district, which has made a impulse buying with accidental sampling. While the analysis of the data processing is done by using SPSS 16.0 for windows. Analysis were performed with existing data using test of validity, reliability, multiple regression analysis, and hypothesis testing using the f test and t test. Based on the results of the analysis it shows that, the three independent variables has significant influence of the dependent and there is one variabel that not significantly influence of the dependent. Positive emotions variable has positive effect of 0.218 with a significance level 0.044, the shopping environment response variable has a positive impact of 0.019 with a significance level of 0.878, the interaction between the customer and sales person variable has a positive effect of 0.310 with a significance level of 0.002, and the hedonic shopping value variable has positive effect of 0.228 with a significance level of 0.008. Coefficient amount of determination R2 of the four variables is 32.3%. This means that the four independent variables simultaneously could explain 31.6% variables on while other variables in the amount of 100% - 32.3% = 67.7% explained by other variables that are not described in this study. It can be recommended that the next research should be examine another variables in this study. Based of the result, the conclussion of this research is positive emotion, shopping environmen response, interaction between customers and sales person and hedonic shopping value are influence on impulse buying Alfamart Banyumanik district Semarang.