Provided are a blood flow displaying method, apparatus and device for an ultrasonic system. The method includes: determining a current pulse recurrence frequency of the ultrasonic system, determining a current extraction factor according to the current pulse recurrence frequency and a preset reference pulse recurrence frequency, extracting a target gradation sequence from a preset gradation set according to the current extraction factor, and displaying a blood flow velocity currently detected by the ultrasonic system using a spectrum of the target gradation sequence.
