A safety valve device is mounted on an inflatable apparatus and has a body, a manual seal assembly and a check valve. The body has an annular sidewall and an annular bracket mounted on the sidewall and having a central opening. The manual seal assembly is connected to the body and has a knob, a seal and a spring. The knob is mounted rotatably on the body and has multiple compression ridges. The seal is mounted slidably between the knob and the annular bracket, selectively closes the central opening and has multiple compression ridges corresponding to those on the knob. The spring biases the seal to open the central opening. The check valve has a diaphragm that selectively closes the central opening. The inflatable apparatus with the safety valve device has a good hermetic effect.