The invention discloses a heart flow field plane streamline visually-describing method based on Doppler image information, comprising the following steps of: extracting a blood flow velocity component in a two-dimensional observation plane along the sound beam direction on the basis of information of a two-dimensional colored Doppler ultrasonic image; calculating a Doppler flow function and a Doppler flow distance function of a two-dimensional detection plane flow field; expressing the three-dimensional flow by using a point source and a point convergence; quantizing the Doppler flow distance function by using a unit flow q and determining the positions of the point source and the point convergence according to the distribution condition of the quantized result and the Doppler blood flow speed; and respectively taking the point source and the point convergence as a starting point and an ending point of a plane flow line and connecting corresponding starting point and ending point according to the equal flow function value of the plane flow and other principles so as to draw the plane flow line. The method can effectively realize the visualized description of the motion state of the heart flow field in a detection plane and lay the foundation for effective visualized observation and accurate quantized evaluation for the fluid mechanics state of the heart flow field.