We propose and demonstrate a simple multiwavelength erbium-doped fiber laser (EDFL) scheme based on a WaveShaper. The WaveShaper can not only act as a multichannel filter but can also introduce wavelength-dependent loss (WDL) in the laser cavity. The WDL can effectively suppress the mode competition caused by the homogeneous gain broadening of the EDF. As a result, up to an 11-wavelength lasing operation with a wavelength spacing of 0.8 nm has been achieved. The power distribution among wavelengths is uniform and the measured power fluctuation of each wavelength is less than 1 dB.