The invention provides a prestressed solid square pile row die and a square pile machining method, and relates to the technical field of prestressed square piles. The prestressed solid square pile rowdie comprises a bottom die body and a plurality of side die bodies, the side die bodies are arranged at intervals in the width direction of the bottom die body, and a reserved space for pouring square piles is formed between every two adjacent side die bodies. A plurality of first mounting holes are formed in the bottom die body, second mounting holes are formed in the side die bodies, and fasteners separately penetrate through the first mounting holes and the second mounting holes to fixedly connect the bottom die body with the side die bodies. The technical problems existing in the prior art that a die cannot manufacture square piles of various specifications is solved.