Hybrid molding is the combining molding process of stamping and injection moldings for Fiber Reinforced Thermoplastics（FRTP）, therefore composite structural materials with mounting members or rib structure behind molding products can be fabricated in a single operation by using the process. However, the effects of molding conditions on the interfacial properties between preheated part and injected resin have not been investigated. In this study, molding products with rib structure were made by using hybrid molding system on a pre-heated woven fabric reinforced thermo-plastic composite prepreg by changing pre-heating temperature of the prepreg and temperature of the injected resin. Interfacial properties between woven composites and injected parts were examined by tensile test. Interfacial strength in injection compression mode was mainly affected by pre-heated temperature of prepreg. Interfacial strength with pre-heating temperature of 300℃ showed highest value and decreased with temperature of prepreg and injected resin over 310℃ due to thermal degradation of resin. Meanwhile, interfacial strength in injection mode was affected by both pre-heated temperature of prepreg and injected resin temperature. Interfacial strength in injection mode increased in line with increase in injected resin temperature up to 300℃.