In order to accomplish the high reliable testing of column stress underspecial circumstances in large forging hydraulic press, a new stress testing system for columns in large forging hydraulic press is proposed. In this system, a non-contact and micro-displacement sensor is used to detect the micro-deformation of the column, and the column stress is measured indirectly according to the strain-stress relationship of the column. In the new system, the analog signals of stress testing are digitalized and transmitted by digital industrial field bus so as to accomplish the long-distance transmission under special circumstances. Experimental study and engineering application are carried out, the results show that the new testing system can substitute the traditional stress testing method which is based on resistance strain gauge and accomplish the high reliable testing of column stress under special circumstances in large forging hydraulic press. At last, some recommendations are proposed, which are helpful in practical use.