A manufacturing method of a thermoplastic composite bicycle frame, and the manufacturing method characterized in comprising the following steps: a shell forming step: turning thermoplastic composite laminates into multiple shells (20A, 20B) by compression molding, wherein the multiple shells (20A, 20B) are capable of being assembled together; each one of the multiple shells (20A, 20B) has a cavity (21A, 21B) surrounded by the shell (20A, 20B), at least one straight segment (22A, 22B) and at least one curved segment (23A, 23B) connected with the at least one straight segment (22A, 22B); the straight segments (22A, 22B) of the multiple shells (20A, 20B) are aligned with one another; the curved segments (23A, 23B) of the multiple shells (20A, 20B) are aligned with one another; each straight segment (22A, 22B) has a straight connecting edge (221A, 221B); and each curved segment (23A, 23B) has a curved connecting edge (231A, 231B); a shell assembling step: assembling the multiple shells (20A, 20B) to make the straight connecting edges (221A, 221B) of the multiple shells (20A, 20B) overlapped with one another and to make the curved connecting edges (231A, 231B) of the multiple shells (20A, 20B) butt jointed with one another rather than being overlapped; and a hot pressing step: through compression molding, turning the overlapped straight connecting edges (221A, 221B) and the butt jointed curved connecting edges (231A, 231B) of the multiple shells (20A, 20B) into multiple fusion areas by heating and compressing so as to connect the multiple shells (20A, 20B) as a bicycle frame component. a shell forming step: turning thermoplastic composite laminates into multiple shells (20A, 20B) by compression molding, wherein the multiple shells (20A, 20B) are capable of being assembled together; each one of the multiple shells (20A, 20B) has a cavity (21A, 21B) surrounded by the shell (20A, 20B), at least one straight segment (22A, 22B) and at least one curved segment (23A, 23B) connected with the at least one straight segment (22A, 22B); the straight segments (22A, 22B) of the multiple shells (20A, 20B) are aligned with one another; the curved segments (23A, 23B) of the multiple shells (20A, 20B) are aligned with one another; each straight segment (22A, 22B) has a straight connecting edge (221A, 221B); and each curved segment (23A, 23B) has a curved connecting edge (231A, 231B); the multiple shells (20A, 20B) are capable of being assembled together; each one of the multiple shells (20A, 20B) has a cavity (21A, 21B) surrounded by the shell (20A, 20B), at least one straight segment (22A, 22B) and at least one curved segment (23A, 23B) connected with the at least one straight segment (22A, 22B); the straight segments (22A, 22B) of the multiple shells (20A, 20B) are aligned with one another; the curved segments (23A, 23B) of the multiple shells (20A, 20B) are aligned with one another; each straight segment (22A, 22B) has a straight connecting edge (221A, 221B); and each curved segment (23A, 23B) has a curved connecting edge (231A, 231B); a shell assembling step: assembling the multiple shells (20A, 20B) to make the straight connecting edges (221A, 221B) of the multiple shells (20A, 20B) overlapped with one another and to make the curved connecting edges (231A, 231B) of the multiple shells (20A, 20B) butt jointed with one another rather than being overlapped; and a hot pressing step: through compression molding, turning the overlapped straight connecting edges (221A, 221B) and the butt jointed curved connecting edges (231A, 231B) of the multiple shells (20A, 20B) into multiple fusion areas by heating and compressing so as to connect the multiple shells (20A, 20B) as a bicycle frame component.