This　paper　firstly　proposes　the　architecture　for　a　distributed　environment　scanning　system,　which　is　based　upon　Multi-Agent.　According　to　the　theory　of　Hierarchical　Timed　Colored　Petri　Nets　(HTCP-net),　a　system　scheduling　model　is　built　with　modeling　and　simulation　tools　CPN　Tools　for　the　priority-based　task　scheduling　algorithm　and　shortest　waiting　queue　dynamic　load　balance　scheduling　algorithm.　Finally,　the　model　executes　for　simulation,　and　demonstrates　average　waiting　time　of　tasks　and　average　length　of　each　agent　waiting　queue.　Compared　with　the　results　from　simulation　of　cyclic　scheduling　algorithm,　it　meets　the　system　demands　of　periodically　repeated　web　page　visit.