The interfaces between five types of reinforcement ultra high performance concrete(UHPC) and normal concrete(NC) were evaluated with respect to their crack resistance, flexural capacity and failure modes by the flexural behavior tests, namely rectangular with holes, rectangular with high reinforcement, wedge shaped and diamond shaped reinforcement interfaces. The influences of treatments of NC surface, moisture degrees of NC, ages of UHPC and curing conditions on the crack resistance of UHPC NC interface were investigated by the NC UHPC NC specimens direct tensile tests. The results demonstrate that cracking strength and flexural capacity of the reinforcement interfaces between UHPC and precast NC are better than that in the intact NC deck. The failure occurs in the precast NC components in most cases. The roughened or concave convex NC surfaces, saturated by NC substrate and 60℃ steam curing can significantly improve the crack resistance of the interface, the 861% of 28d cracking strength of the UHPC NC interface can be achieved at the early age of 37d, and cracking strength developes slowly after 28d.