The utility model relates to a portable mechanical property testing machine for a stretching and twisting composite material. According to the portable mechanical property testing machine, a pull force seat set is fixed with a tension sensor and a chuck, wherein the pull force seat set is fixed on a guide rail slide block and is matched with the chuck at the opposite side to work; power transmission mechanisms including a gear, a worm wheel and worm rod, a screw rod nut and the like are combined with motors to respectively realize functions of unidirectional stretching and unidirectional twisting. The two motors are respectively used for controlling two motions and relative data is acquired by the tension sensor, a torque sensor and an electronic ruler; the control of all the motions, data analysis and curve drawing are controlled by computer programs. The portable mechanical property testing machine can be placed on a teacher projector to carry out clear observation and is also suitable for teaching material object demonstration of many engineering lesson theory classes. The portable mechanical property testing machine is small in whole size, ingenious in appearance and strong in practicability.