A single-polysilicon layer non-volatile memory having a floating gate transistor, a program gate and a control gate is provided. The floating gate transistor has a floating gate and a tunneling dielectric layer. The floating gate is disposed on a substrate. The tunneling dielectric layer is disposed between the floating gate and the substrate. The program gate, the control gate and the erase gate are respectively disposed in the substrate under the floating gate separated by the tunneling dielectric layer. Therefore, during a program operation and an erase operation, charges are injected in and expelled out through different regions of the tunneling dielectric layer, so as to increase reliability of the non-volatile memory.