Bistability in a single-mode distributed feedback semiconductor laser (DFB-SL) with positive optoelectronic feedback (POEF) is observed experimentally. For a given biased current, the output dynamical states of DFB-SL with POEF are critically dependent on variation routes of the laser-biased current. Different routes of biased current variation lead to a bistability characterized by states of different time series, power spectra, and phase portraits.