Recent　studies　have　revealed　that　space　beam　interferenced　in　the　gain　medium　would　result　in　space　burning　hole　phenomenon　and　form　the　gain　grating.　The　gain　grating　formed　by　the　four-wave　mixing　function　after　multiple　oscillations　in　the　resonator　has　self-adaptive,　self-Q-switched　and　spatial　filtering　capabilities,　and　can　obtain　holographic　conjugate　output.　Based　on　the　above　characteristics　of　the　gain　gratings　in　a　non-reciprocal　laser　cavity　with　a　grazing　incidence　structure,　we　analyze　the　factors　which　affect　the　output　single-frequency　stability　and　output　energy　with　diode-pumped　monolithic　Nd:YVO4　crystal,　and　achieve　a　single-longitudinal-mode　Q-switched　output　with　a　single　pulse　energy　of　0.9　mJ,　a　pulse　width　of　7.5　ns,　and　a　line　width　of　0.95　pm　by　optimizing　the　extinction　ratio　of　the　non-reciprocal　element,　the　gain　area,　the　size　of　self-intersecting　angle　and　other　conditions.　As　far　as　reviewed,　this　is　the　maximum　energy　achieved　by　the　current　monolithic　gain　media,　which　can　provide　references　for　analyzing　and　optimizing　the　single-longitudinal　mode　oscillations　to　achieve　stable　non-reciprocal　gain　grating　lasers.　©　2018,　Chinese　Lasers　Press.　All　right　reserved.