At　present,　with　the　increase　of　automated　attack　tools　and　the　development　of　the　underground　industrial　chain　brought　by　network　attack,　even　well-managed　network　is　vulnerable　to　complex　multi-step　network　attack,　which　combines　multiple　network　vulnerabilities　and　uses　the　causal　relationship　between　them　to　achieve　the　attack　target.　The　detection　of　such　attack　intention　is　very　difficult.　Therefore,　in　order　to　solve　the　problem　that　the　real　attack　intention　of　the　attackers　in　complex　network　is　difficult　to　be　recognized,　this　paper　proposes　to　assume　the　possible　targets　in　the　network　according　to　the　important　asset　information　in　the　network.　By　constructing　the　hierarchical　attack　path　graph,　the　probability　of　each　hypothetical　attack　intention　target　is　calculated,　and　the　real　attack　intention　and　the　most　likely　attack　path　of　the　attacker　are　deduced.　The　hierarchical　attack　path　graph　we　use　can　effectively　overcome　the　cognitive　difficulties　caused　by　network　complexity　and　large　scale,　and　can　quantitatively　and　qualitatively　analyze　the　network　status.　It　is　of　great　importance　to　make　the　protection　and　strategy　of　network　security.