Agreement　enterprise　reserve　mode　is　one　of　the　effective　ways　for　governments　to　improve　the　level　of　emergency　supplies　reserve　and　ensure　the　supply　capacity.　In　this　reserve　model,　the　choice　of　reserve　methods　(physical　reserves　and　production　capacity　reserves),　the　corresponding　quantity　of　emergency　supplies　and　government　procurement　pricing　are　the　three　core　issues.　Therefore,　based　on　a　quantity　flexible　contract,　the　paper　constructs　a　model　of　emergency　supplies　stored　by　agreement　enterprises,　and　studies　the　corresponding　reserve　decision　and　procurement　pricing.　After　giving　the　optimal　decision　of　both　parties,　the　paper　finds　that　the　probability　of　sudden　disasters　in　the　reserve　cycle　and　the　spot　market　price　have　important　influences　on　the　decision-making　of　both　parties,　and　further　analyzes　the　impact　of　these　factors　on　the　government’s　cost　and　enterprise’s　profit,　which　can　provide　scientific　guidance　and　basis　for　the　cooperation　between　governments　and　enterprises　to　carry　out　the　emergency　supplies　reserve.　Finally,　the　paper　verifies　the　conclusions　by　numerical　simulation.　©　2020,　Editorial　Board　of　Journal　of　Systems　Engineering　Society　of　China.　All　right　reserved.