Abstract: A soliton mode-locked erbium-doped fiber laser (EDFL) was reported using copper oxide (CuO) material as a saturable absorber (SA). The CuO material was prepared by liquid phase precipitation method and deposited on the tapered fiber as a passive mode-locked device. When the pump power was 233.6 mW, the traditional soliton pulses with a pulse width of 1.23 ps were obtained at the central wavelength of 1 530.2 nm, with a basic repetition frequency of 5.34 MHz and the pulse energy as well as average output power of 1.37 nJ and 2.2 mW, respectively. In addition, when the pump power was increased to 329 mW, the bound-state soliton pulses were first observed at the central wavelength of 1 529.6 nm, with a spectral modulation period of 3 nm and a pulse separation of 2.6 ps. The results show that the CuO materials are good SA candidates for ultrafast fiber lasers.