A measurement method of subcell photocurrents and a matching degree of the subcell photocurrents of a multi-junction photovoltaic cell, comprising: measuring an I-V characteristic of the multi-junction photovoltaic cell to obtain an I-V curve of the multi-junction photovoltaic cell; and measuring currents corresponding to respective current steps in the I-V curve to obtain approximate values of short-circuit currents of subcells in the multi-junction photovoltaic cell, and then calculating a mismatching degree of the currents to obtain a current mismatching degree of the multi-junction photovoltaic cell, wherein to obtain the I-V curve the method comprises irradiating the multi-junction photovoltaic cell using a light source having a stable output power and meanwhile scanning the multi-junction photovoltaic cell within a set voltage scanning range, wherein the set voltage scanning range is from a reverse bias voltage to a forward bias voltage, specifically from a reverse breakdown voltage to a forward open-circuit voltage of the multi-junction photovoltaic cell, or the set voltage scanning range is from a forward bias voltage to a reverse bias voltage, specifically from a forward open-circuit voltage to a reverse breakdown voltage of the multi-junction photovoltaic cell; characterized in that the method further comprises connecting positive and negative electrodes of the multi-junction photovoltaic cell with a high-precise source meter using a four-wire method; placing the multi-junction photovoltaic cell within a coverage of a light spot; and setting and turning on the light source and meanwhile scanning the multi-junction photovoltaic cell from the reverse bias voltage to the forward bias voltage or from the forward bias voltage to the reverse bias voltage to obtain the I-V curve. measuring an I-V characteristic of the multi-junction photovoltaic cell to obtain an I-V curve of the multi-junction photovoltaic cell; and measuring currents corresponding to respective current steps in the I-V curve to obtain approximate values of short-circuit currents of subcells in the multi-junction photovoltaic cell, and then calculating a mismatching degree of the currents to obtain a current mismatching degree of the multi-junction photovoltaic cell, wherein to obtain the I-V curve the method comprises irradiating the multi-junction photovoltaic cell using a light source having a stable output power and meanwhile scanning the multi-junction photovoltaic cell within a set voltage scanning range, wherein the set voltage scanning range is from a reverse bias voltage to a forward bias voltage, specifically from a reverse breakdown voltage to a forward open-circuit voltage of the multi-junction photovoltaic cell, or the set voltage scanning range is from a forward bias voltage to a reverse bias voltage, specifically from a forward open-circuit voltage to a reverse breakdown voltage of the multi-junction photovoltaic cell; characterized in that the method further comprises connecting positive and negative electrodes of the multi-junction photovoltaic cell with a high-precise source meter using a four-wire method; placing the multi-junction photovoltaic cell within a coverage of a light spot; and setting and turning on the light source and meanwhile scanning the multi-junction photovoltaic cell from the reverse bias voltage to the forward bias voltage or from the forward bias voltage to the reverse bias voltage to obtain the I-V curve.