The term “Big data” related to data that is huge in amount, fast to access or complex. A huge amount of data is generated day by day. The Big Data and its analysis play an important role in the world of IT with other applications like cloud computing, data mining, IoT etc. As the internet and digital technologies are growing, the amount of data is also increasing day by day. But this amount of data cannot be processed by using traditional methods. A lot of effort is required to analyse this amount of data. But while ensuring data security and privacy, many challenges are there like protection against security breaches and data leakage, vulnerabilities in public databases and third-party data sharing etc. The objective of this paper is to discuss various applications and security issues with Block chain solution of Big Data challenges.