Abstract: High frequency ultrasound imaging is a hotspot in medical ultrasound imaging due to its high resolution and good real-time performance. However, the attenuation of ultrasound increases exponentially with the frequency, the amplitude of high-frequency ultrasonic signal is usually small and the signal-to-noise ratio of image is low. In order to enhance the signal-to-noise ratio (SNR) of high frequency ultrasound imaging, in recent years, the encoding transmission techniques have been increasingly studied and applied. In this paper, the encoding transmission techniques in the applications of high frequency ultrasound imaging are summarized. By reviewing the recent research progress of different encoding transmission techniques both at home and abroad, three main techniques with Chirp code, Barker code and Golay code in high frequency ultrasound imaging are emphatically analyzed. Also, the application prospects of various encoding transmission techniques in medical high frequency imaging are compared.