The invention discloses a water purifying device with a filter element conveniently changed. The water purifying device comprises a water tank, a supporting plate is fixedly connected with the bottom of the left side of the water tank, a water pump is arranged at the top of the supporting plate, a water inlet of the water pump is communicated with a water inlet pipe, and a water outlet of the water pump is communicated with a first water outlet pipe. The right end of the first water outlet pipe runs through the water tank and extends into the water, a partition plate is fixedly connected with the left side of the bottom of the inner wall of the water tank, a pin hole is formed in the right side of the bottom of the inner wall of the water tank, and a pin column is arranged in the pin hole. The filter element, a through hole, a connection plate, a cover plate, a seal ring, a cylinder, a clamping rod, a fixing plate, a rotary plate, a rotary shaft and a semicircle pipe are arranged to be matched in use, the effect of conveniently changing the filter element is achieved, the problem that the filter element is inconvenient to change if a water purifier and the filter element are integrated is solved, accordingly a lot of time is saved when a user change the filter element, and the labor intensity of the user is reduced.