The invention provides a data de-interleaver and ultrasonic Doppler method diagnostic equipment of the data de-interleaver, wherein, the de-interleaver can complete de-interleaving of an undersampled data packet. The invention comprises a storage, a write in device, a read device, wherein, the storage is divided into a first part and a second part; the write in device writes a first matrix data packet into the first part of the storage at the frequency of Fs/SSR according to line sequence; moreover, the Fs is a data initial sampling frequency, while the SSR is an undersampling factor; the read device reads the first matrix data packet from the first part at a preset frequency according to column sequence; while the read device reads the first data packet, the write in device writes a second matrix data packet into the second part of the storage at the frequency of Fs/SSR; moreover, the sum of the preset frequency and the frequency Fs/SSR is less than or equal to Fs. The data de-interleaver realized according to the invention can realize maximized read-write efficiency and can be used in data matrix of different sizes, thereby improving flexibility.