Effects of interface roughness and dislocation density on the electroluminescence (EL) intensity of In GaN multiplem quantum wells (MQWs) are investigated. It is found that the EL intensity increases with the number of satellite peaks in the x-ray diffraction experiments of In GaN MQW samples. It is indicated that the rough interface will lead the reduction of EL intensity of In GaN MQW samples. It is also found that the EL intensity increases with the decrease of dislocation density which is characterized by the x-ray diffraction measurements. It is suggested that the EL intensity of In GaN MQWs can be improved by decreasing the interface roughness and dislocation density.