As a major medical imaging technology, medical ultrasound imaging with its many advantages, such as no harm to the human body, real-time cheap and easy to use, is widely used in clinic. But the ultrasonic imaging "speckle" noise makes it difficult to distinguish between normal tissue and pathological tissue. According to the character of noise in the medical ultrasonic image, a new method of the medical ultrasonic imaging filter based on mathematics morphology and adaptive filtering is proposed after analysis of "speckle" noise and general filter ， and an experiment is made to validate. The experimental method is as follows: firstly the Rayleigh noise is imposed on the original image, and then the median filter and the adaptive median filter are used on the contaminated image. Secondly the morphological filter is used to enhance the contrast after pre-processing by the adaptive median filter on the image to retain the necessary details. Finally, the three noise filtering methods are compared from the images denoising and evaluation And the results indicate that the new method is superior to other ones