The invention discloses a test circuit for a resistive sensor array based on a two-wire system isopotential method, and belongs to the technical field of sensors. The test circuit aims at the M*N 2D resistive sensor array in which row and column lines are shared; and the test circuit comprises a current feedback operation amplifier, N column line driving operation amplifiers, an equal current M-to-1 multipath switch, an isopotential M-to-1 multipath switch, N column line 2-to-1 multipath switch, a test current setting resistor, a reference voltage source and two connecting wires, and the connecting wires is used for the row lines and the column lines of the resistive sensor array. The invention also discloses a test method of the test circuit and a sensing system. Compared with the prior art, the test circuit uses the two-wire system isopotential method as key technology, measuring errors caused by lead resistance of connecting cables, contact resistance of cable joints and conduction resistance of multipath switch channels can be eliminated effectively, and the measuring precision of the resistive sensor array is greatly improved.