A verification code generation method is performed in an electronic device which is for performing encoding to generate a video/audio stream having multiple data segments. The verification code generation method includes the following steps. Each time one of the data segments is generated by the encoding, a first-level checksum associated with the data segment is generated, and the first-level checksum is recorded in an accompanying verification file. At an interval of every N data segments of the data segments, a second-level checksum is generated for W consecutive first-level checksums, and the second-level checksum is recorded in the accompanying verification file, such that a subsequent verification method can quickly verify integrity of a part of data according to the accompanying verification file. Wherein, W is a positive integer greater than or equal to 2, N is a positive integer greater than 0 and smaller or equal to W.