The Inductive Approach has been used successfully to analyse Local Area Network protocols, Internet protocols, e-commerce protocols and smart card protocols, But the theorems proofs method is very complex and is very difficult to master. It requires that a user must guide the proof process,and select the tactic to be applied etc. Proofs are cumbersome and security properties are not built into the logic but proven within it, making it difficult to give an account of proof discovery. We simplified Paulson’s inductive approach, referring to the idea of belief logic. Our method formulates the main protocol property based on belief logic. If proven, these guarantees can be combined to provide a story as to why the protocol achieves security. Otherwise, the unproven goals may be used to uncover hidden assumptions or attacks.