This study investigated the factors affecting purchase decisions in electronic commerce by considering transaction costs. Based on prior research, an empirical analysis was conducted on purchase decisions that account for transaction costs in electronic commerce. The study found that human asset specificity, brand specificity, product uncertainty, transaction channel uncertainty, and transaction frequency had significant effects on transaction costs. Furthermore, transaction costs were found to have a significant effect on electronic commerce purchase decisions. Implications and limitations of the paper are discussed in the conclusion.