Against heavy workload and long periodicity caused by dislocation performance testing of load feeling mechanism in operating system in aircrafts, based on modern measuring and controlling theory and technology, “in situ testing instrument for load feeling mechanism in operating system of aircrafts” is designed, which applies sensors, PLC and portable computer. The instrument can generate actual operating characteristic curve in real time with software through detected lengthwise direction and cross direction force and displacement of steering column, then compared with standard operating characteristic curve, performance of load feeling mechanism is evaluated. The tryout of the instrument shows that it can meet the needs of aircrafts maintaining crew because of its accurate detecting, convenient using, in situ and auto testing.