The invention relates to a body fluid cancer marker detection device for a human body. The problems that the conventional detection device is high in manufacturing cost, extremely large in size, complicated in detection, inaccurate in detection result and the like are solved. The body fluid cancer marker detection device comprises magnetic elastic biological test paper, a micro controller, a coil bracket, an enhanced impedance converter, a power circuit, a direct current biasing circuit, a key and a liquid crystal screen, wherein a direct current biasing coil and an alternating current excitation coil are wound on the coil bracket; the magnetic elastic biological test paper is inserted into the coil bracket; a magnetostrictive material thin sheet is arranged on the magnetic elastic biological test paper; an antibody corresponding to a cancer marker to be detected is modified on the magnetostrictive material thin sheet. The magnetostrictive material in the body fluid cancer marker detection device is low in cost, high in sensitivity and high in detection precision; the number of the cancer markers in body fluid can be quickly and accurately detected, and the trouble and the error which are caused by repeated use can be avoided. Furthermore, the body fluid cancer marker detection device is small in size and convenient for portable detection; the noise interference is reduced, and the accuracy and the reliability of detection of the magnetic elastic biological test paper are improved.