Based on the principle of order parameter in synergetics theory, this research applies the synergistic evaluation method to measure the collaborative development between two complex economic subsystems: E-Commerce transactions (ECT) system and express logistics service (ELS) system. We plan to build an evaluation model of coordination index and then conduct an empirical study based on the statistical data between 2005 and 2014. Our research is expected to provide valuable suggestions for promoting the coordinated development between ECT and ELS systems.