A method for picture-based barcode encoding and decoding is provided herein. The method for picture-based barcode encoding includes: transforming an original data into an original data bitstream; performing an error correction on the original data bitstream for translating the original data bitstream into an error corrected bitstream; selecting all or part of the picture as an encoded area; calculating a data storage capacity of the encoded area; adjusting a size of the error corrected bitstream or a size of the encoded area for equalizing a data storage capacity of an encoded data bitstream and the data storage capacity of the encoded area; and adjusting a pixel value of the encoded area according to the encoded data bitstream.