This paper focuses on the position characteristic test of STEP SA1400 industrial robot based on GB/T 126422013“Industrial robotsperformance criteria and related test methods” by using CompuGauge testing system from Dynalog company. Firstly ensure this testing on the foundation laid by GB/T 126422013 “Manipulating industrial robotsperformance criteria and related test methods”. Analyze the primary error of the test after the test finish and compute all parts of uncertainty of the test course. Finally evaluate the position characteristic uncertainty.