This research aims to find out how big the influence of green marketing of the purchase that is mediated by the brand image on Eco-Friendly products Pertamax series. This research was conducted in Yogyakarta. Sampling method used in this research is the nonrobability sampling used is purposive sampling. Total sample in this research as many as 120 people. Data were collected using a questioner. Analysis techniques using path analysis with help of spss 21 software. Results showed that green marketing have positive and significant influence on purchasing decision. Green Marketing have positive and significant influence on brand image.brand image have positive and significant influence on purchasing decision. Brand image mediate the influence of green marketing towards purchasing decisions