To satisfy the need of field measurement of the multi-optical axes parallelism of photoelectronic equipments, a portable axes parallelism calibration system is developed. The collimation of Cassegrain optical system and ZnS reticle is used in the system to create infinite reticle object and to provide aiming baseline for the original system and realising the parallelism calibration between television axis and infrared axis. A CCD system is adopted to collect crosswire on the reticle and laser facula on the target sheet. On the basis of the bias between the detected reticle centre and laser spot centre, parallelism calibration for laser axis and visible axis is achieved. An optical angle gauge is applied in this system to make calibration precision to approach angle second level. Experimental analytical results show that the standard uncertainty of this measurement for the parallelism between the TV-axis and the infrared-axis can reach 2″ and the standard uncertainty of this measurement for the parallelism between the sighting axis and the receiving axis of laser can reach 5″.