Portable dissolved oxygen tester

The utility model provides a portable dissolved oxygen tester. The portable dissolved oxygen tester comprises a fixed column; the fixing box is fixedly installed on one side of the fixing column, and wire outlet holes are formed in the top and the bottom of the fixing box; the rotating rod is rotationally connected to the inner side face of the fixed box, and a take-up wheel is fixedly installed on the outer side face of the rotating rod; the torsional springs are fixedly installed at the two ends of the outer side face of the rotating rod, and one end of each torsional spring is fixedly installed on one side of the inner side face of the fixing box. Preferably, the torsional springs are arranged on the two sides of the take-up wheel respectively, and a data line is wound on the outer side face of the take-up wheel. According to the portable dissolved oxygen tester provided by the utility model, when the portable dissolved oxygen tester is used, a user can conveniently store data lines through the fixing box,