Disclosed is a method and apparatus for controlling a synchronous output of a digital matrix, and an electronic device, which relates to the field of multi-media technology and can control the synchronous outputs of output units. The method includes: when output units are activated or an individual output unit in the output units is re-activated after an abnormality occurs in this individual output unit, calibrating output start times and output periods of the output units such that the output start times of the output units are identical and the output periods of the output units are identical; receiving, by the output units, to-be-processed data based on the identical output start times; and after the to-be-processed data is received, controlling the output units to complete processing of the received to-be-processed data within a current output period, such that the output units output the processed data synchronously in a next output period.