This research aims to determine : The influence of Brand Equity on Purchasing Decision. This resarch method used in this study is explanatory research with quantitative approach. Two hypotheses are formulated related to the research objectives. Independent variables used in this study are Brand Awareness, Brand Associations, Perceived Quality, Brand Loyalty and dependent variable is Purchase Decision. The sampling technique used is accidental sampling. Data collected by using a questionnaire with total sample 106 respondents who are buyer and user simPATI Telkomsel sim card. Analysis of the data used is descriptive analysis and multiple linear regression analysis which is processed using SPSS version 22.00. The result of this research shows that : simultaneously brand equity has significant influence on purchasing decision, partially the variables of brand equity showed significantly result on purchasing decision except brand awareness, it also found that brand associations have dominant influence. Based on this research it is suggested on Telkomsel company to maintain and improve brand equity about simPATI sim card especially from brand associations.