Bargain position and trust are core issues in supply chain management, yet the effect of bargain position on trust remains to be undetermined. The purpose of this research is to present theoretical and methodological hurdles for the relationship among various bargain positions and trust, and develops a set of hypotheses about the asymmetric effect of bargain position on trust in supply chain network. An analytical tool to analyze nonlinear effects on a response surface is introduced. Based on the data collected through a survey of firms participating in Project Supply chain, a set of hypotheses is tested. The analysis results support the prediction that the bargain position perceived by the buyers have asymmetric effects on trust toward supplies, and provide more fine-grained accounts on the relationships among bargain power, bargain position and trust in a supply chain network.