Timing constraints verification (such as time consistency) for service flow has become indispensable since many services for e-business are distributed in different places with temporal context. Unfortunately, current researches mainly focus on the modeling, analyzing and verifying of service processes, while ignoring temporal factors. To address the challenges of temporal properties verification for service, the paper presents a method for verifying time constraints consistency of service flow. By building time ontology based on DAML_Time, OWL_S is extended with time constraints, which expresses time information of service flow clearly and roundly. Then the annotated OWL_S is transformed to some kinds of formal models and verification algorithm is presented. A prototype system MC4WST is also designed to prove feasibility of the verification process.