An endoscopic ultrasound imaging system based on coded excitation and pulse compression is designed, which can improve the image quality and compensate the deficiency of small echo and high attenuation due to the underdeveloped manufacture technics of the catheter type probe. This system includes probe drive unit, data processing and cache unit, and interactive unit and display unit. In order to suppress the sidelobe caused by the pulse compression,three sidelobe suppression filters are designed. The simulation results show that, for the 4-bit Barker code, the sidelobe can be effectively suppressed by using the mismatch filtering methods. Furthermore, the mainlobe and the peak sidelobe level are able to achieve 0.2 mm and -55 dB with the spike filter method. Finally, an endoscopic ultrasound imaging experimental system was set up, using the target lines as sample, achieved the images with 1 024×1 024 image size and 25 frames per secend speed, which proved the feasibility of the system and the correctness of the above conclusions.