This study aims to determine the effect of online service quality on purchasing decisions of fresh vegetables on the Instagram account @Sayur_Segar_Mataram. This research is a quantitative study with an associative approach. Data collection was carried out through the distribution of questionnaires to respondents who had previously made purchases, with the analysis technique using multiple linear regression through the Statistical Package for the Social Sciences (SPSS). The results of the study indicate that online service quality, which consists of system reliability, responsiveness, security assurance, empathy, and digital physical evidence, simultaneously has a significant effect on purchasing decisions. Partially, all variables also have a significant effect on purchasing decisions, with empathy being the most dominant variable. The coefficient of determination (R²) of 0.633 indicates that 63.3% of the variation in purchasing decisions can be explained by online service quality variables, while the remaining is influenced by other variables outside this study. The instrument test results show that the data are valid and reliable, and have met the classical assumption tests, indicating that the regression model is feasible to use. These findings suggest that the better the online service quality provided, the higher the consumer purchasing decisions for fresh vegetable products. It is recommended that the management of the @Sayur_Segar_Mataram account continue to improve service quality, especially in terms of empathy, responsive communication, and product visual appearance in order to increase consumer trust and purchase intention. Future researchers are suggested to include other variables such as price, customer satisfaction, and trust in order to obtain more comprehensive results.