The invention discloses a degradation testing device for a perovskite photovoltaic cell. The device is characterized in that a vacuum cavity is a closed box body; a vacuum system consisting of a mechanical pump and a molecular pump is arranged on the box body; a heating table and a movable bracket which are connected with a temperature controller are arranged in the box body; the mechanical pump and the molecular pump are respectively connected with an isolation cabin and a vacuum cavity through vacuum tubes; the heating table is arranged on a sample table and is connected with the temperaturecontroller arranged outside the vacuum cavity; the movable bracket is arranged between the sample table and an isolation cabin for conveying samples, and one end of the movable bracket is fixed at the top of the vacuum cavity; the vacuum cavity is provided with a vacuum gauge/water oxygen probe, an external light source, an air inlet valve and a J-V test interface. Compared with the prior art, the device has the advantages that different working environments and testing conditions of perovskite can be simulated, degradation testing of perovskite can be accelerated through the adjustable vacuum degree of the cavity, the outer space environments of different heights can be simulated, and the application prospect of perovskite photovoltaic cells in the space field is explored.