A　rate　equation　model　of　multi-quantum　wells　and　multi-active　regions　were　presented.　The　effects　of　photon　density　and　the　carrier　capture-escape-tunnel　time　on　the　frequency　response　of　single　active　region　vertical-cavity　surface-emitting　Laser　(VCSEL)　and　tunnel-regenerated　VCSEL　with　two　active　regions　were　simulated　by　the　small　signal　analysis.　The　result　of　simulation　shows　that　the　modulate　bandwidth　of　tunnel-regenerated　VCSEL　with　two　active　regions　is　larger　than　that　with　single　active　region　under　the　same　drive　current,　then　its　causes　are　discussed.　Moreover,　we　simulate　the　frequency　response　of　the　parasitic　circuit　of　tunnel-regenerated　internal-contact　oxide-confined　VCSEL　with　two　active　regions　after　analyzing　its　parasitic　parameters.