A pressure relief valve, comprising: a valve seat configured to be attached to an inflatable device; and a valve body, wherein the valve body is disposed at least partially within the valve seat and comprises: a valve shell comprising therein a vent hole, a valve diaphragm disposed at a bottom of the valve shell, the valve diaphragm moveable between a closed position in which the valve diaphragm closes the vent hole and an open position in which the valve diaphragm opens the vent hole, a spring biased to push the valve diaphragm into the closed position, and a valve diaphragm fixing part disposed around the vent hole and connected to the valve shell, wherein the valve body further comprises a first spring seat and a second spring seat, with the spring disposed between the first spring seat and the second spring seat, and wherein: the first spring seat is connected to the valve diaphragm and is biased by the spring in a longitudinal direction of the valve diaphragm fixing part to press the valve diaphragm into the closed position, the second spring seat is connected to the valve diaphragm fixing part and is adjustable to thereby limit a compression amount of the spring. characterized in that: one of the first spring seat and the valve diaphragm fixing part comprises a chute therein, and another of the first spring seat and the valve diaphragm fixing part comprises a protrusion portion corresponding to the chute, the chute configured to enable the protrusion portion to move within the chute along the longitudinal direction of the valve diaphragm fixing part and to restrict relative rotation between the first spring seat and the valve diaphragm fixing part. a valve seat configured to be attached to an inflatable device; and a valve body, wherein the valve body is disposed at least partially within the valve seat and comprises: a valve shell comprising therein a vent hole, a valve diaphragm disposed at a bottom of the valve shell, the valve diaphragm moveable between a closed position in which the valve diaphragm closes the vent hole and an open position in which the valve diaphragm opens the vent hole, a spring biased to push the valve diaphragm into the closed position, and a valve diaphragm fixing part disposed around the vent hole and connected to the valve shell, wherein the valve body further comprises a first spring seat and a second spring seat, with the spring disposed between the first spring seat and the second spring seat, and wherein: the first spring seat is connected to the valve diaphragm and is biased by the spring in a longitudinal direction of the valve diaphragm fixing part to press the valve diaphragm into the closed position, the second spring seat is connected to the valve diaphragm fixing part and is adjustable to thereby limit a compression amount of the spring. characterized in that: one of the first spring seat and the valve diaphragm fixing part comprises a chute therein, and another of the first spring seat and the valve diaphragm fixing part comprises a protrusion portion corresponding to the chute, the chute configured to enable the protrusion portion to move within the chute along the longitudinal direction of the valve diaphragm fixing part and to restrict relative rotation between the first spring seat and the valve diaphragm fixing part. a valve shell comprising therein a vent hole, a valve diaphragm disposed at a bottom of the valve shell, the valve diaphragm moveable between a closed position in which the valve diaphragm closes the vent hole and an open position in which the valve diaphragm opens the vent hole, a spring biased to push the valve diaphragm into the closed position, and a valve diaphragm fixing part disposed around the vent hole and connected to the valve shell, wherein the valve body further comprises a first spring seat and a second spring seat, with the spring disposed between the first spring seat and the second spring seat, and wherein: the first spring seat is connected to the valve diaphragm and is biased by the spring in a longitudinal direction of the valve diaphragm fixing part to press the valve diaphragm into the closed position, the second spring seat is connected to the valve diaphragm fixing part and is adjustable to thereby limit a compression amount of the spring. the first spring seat is connected to the valve diaphragm and is biased by the spring in a longitudinal direction of the valve diaphragm fixing part to press the valve diaphragm into the closed position, the second spring seat is connected to the valve diaphragm fixing part and is adjustable to thereby limit a compression amount of the spring. characterized in that: one of the first spring seat and the valve diaphragm fixing part comprises a chute therein, and another of the first spring seat and the valve diaphragm fixing part comprises a protrusion portion corresponding to the chute, the chute configured to enable the protrusion portion to move within the chute along the longitudinal direction of the valve diaphragm fixing part and to restrict relative rotation between the first spring seat and the valve diaphragm fixing part. one of the first spring seat and the valve diaphragm fixing part comprises a chute therein, and another of the first spring seat and the valve diaphragm fixing part comprises a protrusion portion corresponding to the chute, the chute configured to enable the protrusion portion to move within the chute along the longitudinal direction of the valve diaphragm fixing part and to restrict relative rotation between the first spring seat and the valve diaphragm fixing part.