An assembled picture frame is an integral rectangular picture frame formed by fixing four frame strips through four corner fixing parts. The upper side part of each frame strip is provided with a lightening hole wrapped by borders on the periphery, wherein a rectangular corner fixing part inserting hole is formed below the lightening hole, a triangular upper hook inclining downwards is arranged at the intersecting corner of the border at the top and the vertical border of the lightening hole, a lower hook inclining upwards is externally arranged at the position, between the lightening hole and the corresponding corner fixing part inserting hole, of the border, and a trapezoidal cushion block inserting groove is formed between the upper hook and the lower hook; a spring piece inserting groove is formed between the corner of the end of the outer edge of the bottom border of each corner fixing part inserting hole and the corresponding lower hook. Each corner fixing part is composed of an L-shaped upper piece, an L-shaped lower piece and two limiting bolts, and the two arms of each corner fixing part are inserted into the corner fixing part inserting holes of the two corresponding adjacent frame strips respectively. The picture frame is free from mortise joint, firm, steady, rigorous and simple in structure and convenient to assemble and disassemble and has reusability.