Gate-source-drain current test circuit and method, test system and readable storage medium

The invention provides a gate-source-drain current test circuit and method, a test system and a readable storage medium. The method comprises the following steps: grounding a grid electrode of a transistor, and applying a negative voltage to a source electrode; and when the negative voltage reaches a preset value, measuring a current value between the grid electrode and the source electrode as a grid-source-drain current. According to the transistor, the grid electrode of the transistor is grounded, on one hand, the junction capacitance of the grid electrode is continuously and rapidly discharged, on the other hand, the voltage of the grid electrode is set to be zero potential, negative voltage is applied to the source electrode, and it can be guaranteed that an equivalent forward voltage difference is formed between the grid electrode and the source electrode. And in the process of adjusting the forward voltage difference between the grid electrode and the source electrode, in view of the zero potential, the