Carbon epoxy composite bars were used to the thrust stents of the new launch vehicle. According to the filament winding process and characteristics of the tubular parts, this paper presents the method of bottom reflec鄄 tion to detect composite tubular based on the comparison of the conventional ultrasonic testing method. Using ultra鄄 sound C scanning system, this paper adopts the method to artificial defects and the actual products detection. The re鄄 sults show that the detection method can detect the artificial defects accurately, and achieve the product internal defect detection effectively.