The invention discloses a composite structure gel ink pen having measuring, drawing and correction functions. The composite structure gel ink pen comprises a pen rod, wherein the pen rod consists of a first rod body and a second rod body of which the upper ends are hinged; the first rod body is internally provided with a pen refill, and is made of transparent plastic; a sharp pin is arranged at the lower end of the second rod body; and a correction tape is arranged at the upper end of the pen rod. The composite structure gel ink pen has the advantages that the composite structure gel ink pen integrates a gel ink pen part, the correction tape and a pair of compasses, and effectively avoids the embarrassment of a user forgetting to take the correction tape; the composite structure gel ink pen is internally provided with the pen refill, the first rod body is hinged to and is fit with the second rod body, the first rod body and the second rod body are folded to act as the pen rod of the composite structure gel ink pen for use and are separated to act as the compasses for use; the composite structure gel ink pen is simple and reasonable in structure, and is very convenient to use; and the first rod body is made of transparent plastic, so that the use condition of the internal pen refill can be observed at any time and can be replaced timely.