This study attempts to study the relationship between service marketing mix and customer decision making of domestic express courier service. This study employed convenience sampling to collect data. A total of 400 usable samplings of e-marketplace customers are obtained. The findings reveal that the predictor variables of service (β = 0.356, t = 6.341, P = 0.000), and place (β = 0.363, t = 4.872, P = 0.000), people (β = 0.168, t = 3.187, P = 0.002), and process (β = 0.151, t = 3.317, P = 0.001) are achieved significance.