The synchronously pumped femtosecond optical parametric oscillator (OPO) based on was periodically poled 5-mol.% MgO-doped lithuium niobate was demonstrated by means of non-critical quasi phase matching. The femtosecond OPO is cable of operating at room temperature and shows no photorefractive damage. The spectrum can be tuned by varying the cavity length up to 70 £gm, the temperature of the nonlinear crystal from room temperature to 150¢J, and the grating periods. The cavity was designed to resonate at 1.33 £gm with bandwidth of 100 nm. The maximum output intensity of the signal is 43 mW with TEM00 mode. The signal slope efficiency is 11%. The spectrum range of the idler is tunable from 1.8 to 2.8 £gm.