We as a whole realize that blockchain is a procedure of bitcoin which is one of the most well-known technique for digital money that permit circulated add just open record all exchanges to be recorded. Appropriated agreement convention which depends on motivating force good evidence of work gives abnormal state of security this all framework and is controlled by a system hub called miners. Miners sincerely keep up the blockchain so as to get motivators. Bitcoin dispatch in 2009, its economy has developed at a tremendous rate, and it is presently worth about170 billions of dollars. This widespread rise in the market estimation of bitcoin incite enemies to achieve bad marks for benefit, and specialists to find new presentation in the framework, propose cure, and anticipate up and coming procedure. In this chapter, we present a dealt with examination that covers the security and assurance parts of bitcoin. Our strategy initially started from chart of Bitcoin Protocol, second critical portions of bitcoin, third parts convenience and last sections interchanges inside the system. The present chapter in bitcoin and its fundamental noteworthy progressions, for instance, blockchain-based agreement tradition lead to the execution of various security perils to the normal handiness of bitcoin. We discuss about the handiness and soundness of the front-line security courses of action. Moreover, we present current assurance and absence of definition examinations in bitcoin and analyze the security-related threats to bitcoin customers close by the examination of the 224present security shielding courses of action. Finally, we format the essential open troubles and propose rules for future research toward furnishing firm security and assurance frameworks for bitcoin.