A simple,stable wavelength tunable passively mode-locked erbium-doped fiber ring laser is reported. The nonlinear polarization rotation effect is used, as equivalent saturable absorber, to achieve the self-starting mode-locking in the laser. The wavelength tuning can be realized by simply rotating the orientation of polarization controllers. The output of the laser is taken via a wideband coupler, whose operating wavelength is 1550±50 nm. Experimentally, low self-starting threshold mode-locked pulses at 10.23 MHz repetition rate were obtained. The output wavelength was continuously tunable from 1548.64 nm to 1600.24 nm, and the side-mode suppression ratio was beyond 44 dB.