In　recent　decades,　many　brain-computer　interface　(BCI)　software　platforms　have　emerged.　However,　there　are　still　some　limitations.　First,　integrating　an　algorithm　on　online　BCI　software　platform　is　difficult　and　time-consuming.　Second,　there　is　no　guarantee　that　an　unproven　algorithm　will　work　properly.　Last,　existing　platforms　do　not　support　automatic　recording　of　result　metrics　during　experiments,　and　frequent　validation　of　multiple　algorithms　is　inefficient.　In　this　paper,　we　designed　a　novel　BCI　experiment　simulation　platform　(BESP)　based　on　offline　analysis　to　satisfy　the　needs　of　algorithm　validation.　BESP　reorganizes　the　experimental　steps　and　provides　some　interfaces,　which　makes　algorithm　validation　simple　and　efficient.　In　addition,　BESP　is　able　to　record　the　results　produced　during　the　experimentation.　Then　the　results　of　multiple　algorithms　can　be　easily　analyzed,　compared　and　visualized　by　the　statistical　analysis　system　provided　by　BESP.　With　these　characteristics,　BESP　is　able　to　verify　the　correctness　of　the　algorithm.　Finally,　we　designed　a　simulated　P300　spelling　experiment　based　on　BESP,　and　completed　the　validation　and　analysis　of　Algorithms　SPLUCB　and　TSPLUCB　(based　on　PLUCB　and　TPLUCB).　Furthermore,　we　used　BESP　to　analyze　the　differences　between　the　stimulus　signals　of　the　20　subjects.　Through　the　analysis,　we　found　some　areas　worthy　of　further　study.　In　summary,　BESP　is　well　suited　for　the　process　of　analysis,　optimization　and　validation　among　multiple　algorithms.　©　2023　IEEE.