A pressure swing adsorption-type oxygen concentration device comprising: two adsorption cylinders packed with an adsorbent that selectively adsorbs nitrogen rather than oxygen; a compressor configured to supply compressed air to the adsorption cylinder; a flow path switching means that is configured to repeat, by sequentially switching a flow path between the compressor and each adsorption cylinder, at a prescribed timing, an adsorption step where pressurized air is supplied to each adsorption cylinder and an oxygen-concentrated gas is taken out, a desorption step where each adsorption cylinder is decompressed and the adsorbent is regenerated, and a purge step where the oxygen-concentrated gas from an adsorption cylinder at an adsorption step side is introduced to the other adsorption cylinder at a desorption step side, wherein the flow path switching means is configured such that the steps of the two adsorption cylinders are in opposite phase to each other so that, while the adsorption cylinder is performing the adsorption step, the other adsorption cylinder performs the desorption step; a flow rate setting means that is configured to supply the oxygen-concentrated gas by adjusting the flow rate to a desired value; and a control means that is configured to control operation of an oxygen concentration sensor configured to measure a concentration of the oxygen-concentrated gas, a pressure sensor configured to detect a pressure of the adsorption cylinder, the compressor and the flow path switching means, characterized in that the control means is configured to control the number of revolutions of the compressor based on a detected value of the oxygen concentration sensor, judge deterioration due to moisture adsorption based on the detected value of the oxygen concentration sensor, a detected value of the pressure sensor, and an operating time of the adsorption cylinder, and when criteria for judgment of deterioration due to moisture absorption are satisfied, control a switching time of the flow path switching means so that a time for the purge step becomes shorter than an initially set value wherein the criteria for judgment of the deterioration due to moisture absorption are to satisfy all three conditions: that the detected value of the oxygen concentration sensor is not more than a prescribed concentration value; that the operating time of the adsorption cylinder is not less than a prescribed time; and that the detected value of the pressure sensor increases to a prescribed value or higher. two adsorption cylinders packed with an adsorbent that selectively adsorbs nitrogen rather than oxygen; a compressor configured to supply compressed air to the adsorption cylinder; a flow path switching means that is configured to repeat, by sequentially switching a flow path between the compressor and each adsorption cylinder, at a prescribed timing, an adsorption step where pressurized air is supplied to each adsorption cylinder and an oxygen-concentrated gas is taken out, a desorption step where each adsorption cylinder is decompressed and the adsorbent is regenerated, and a purge step where the oxygen-concentrated gas from an adsorption cylinder at an adsorption step side is introduced to the other adsorption cylinder at a desorption step side, wherein the flow path switching means is configured such that the steps of the two adsorption cylinders are in opposite phase to each other so that, while the adsorption cylinder is performing the adsorption step, the other adsorption cylinder performs the desorption step; a flow rate setting means that is configured to supply the oxygen-concentrated gas by adjusting the flow rate to a desired value; and a control means that is configured to control operation of an oxygen concentration sensor configured to measure a concentration of the oxygen-concentrated gas, a pressure sensor configured to detect a pressure of the adsorption cylinder, the compressor and the flow path switching means, characterized in that the control means is configured to control the number of revolutions of the compressor based on a detected value of the oxygen concentration sensor, judge deterioration due to moisture adsorption based on the detected value of the oxygen concentration sensor, a detected value of the pressure sensor, and an operating time of the adsorption cylinder, and when criteria for judgment of deterioration due to moisture absorption are satisfied, control a switching time of the flow path switching means so that a time for the purge step becomes shorter than an initially set value wherein the criteria for judgment of the deterioration due to moisture absorption are to satisfy all three conditions: that the detected value of the oxygen concentration sensor is not more than a prescribed concentration value; that the operating time of the adsorption cylinder is not less than a prescribed time; and that the detected value of the pressure sensor increases to a prescribed value or higher.