Passively　Q-switched　nanosecond　pulsed　erbium-doped　fiber　laser　based　on　MoS2　saturable　absorber　(SA)　is　experimentally　demonstrated.　The　high　quality　MoS2　SA　deposited　on　the　broadband　high-reflectivity　mirror　with　a　large　modulation　depth　of　9%　was　prepared　by　pulsed　laser　deposition　method.　By　inserting　the　MoS2　SA　into　an　erbium-doped　fiber　laser,　stable　Q-switched　operation　can　be　achieved　with　the　shortest　pulse　width　of　660　ns,　the　maximum　pulse　energy　up　to　152　nJ　and　pulse　repetition　rates　varying　from　116　to　131　kHz.　The　experimental　results　further　verify　that　MoS2　possesses　the　potential　advantage　for　stable　Q-switched　pulse　generation　at　1.5　mu　m.　(C)　2015　Optical　Society　of　America