The invention discloses a method and a device for removing pollutants in water by freezing precipitation and pressure reverse osmosis. On the basis of a freezing purification principle and a pressurereverse osmosis principle of precipitating the pollutants by water freezing in the sewage freezing process, proper freezing temperature is selected and proper freezing rate is controlled by adopting atop-bottom one-way freezing mode according to the freezing precipitation characteristic of the pollutants; the pollutants are gradually removed by freezing from top to bottom, and finally bottom residual high-concentration pollutants are centrally and chemically treated, so that adverse influence of high cost, secondary pollution hazards and the like of a current chemical treatment mode is avoided. The technology fully utilizes the function of precipitating impurities by water freezing and phase change, and cooling energy only needs to be inputted into a solution. The method and the device have the advantages of high purification degree, no pollution, simplicity and convenience in operation, high cost performance and the like.