In this paper, the authors mainly intend to clarify the relation between NP and PP . A randomized version of NP is given. Based on this equivalent definition of NP , another randomized complexity class is given: SUPER-NP . Although the SUPER-NP is very close to NP , but it is found surprisingly that PP?SUPER NP and thus NP?PP?SUPER-NP . In light of NP=PCP(log, O(1)) and the closeness of NP and SUPER-NP it is hoped that PP?PCP(log²,O(1)) conjecture can be peoved by showing that SUPER-NP?PCP(log²,O(1)).