With fastest development in communication technologies, Internet of Things (IoT) plays a key role with full maturity and its infancy. Rapidly, it has developed (growth) for large data transmission over the wireless communication. Hence, it is needed to manage system and full fill the market requirement for practical application. Many existing IoT has greatly centralized architectures that have many technical limitations. Examples of these limitations are cyber attacks. Hence, it is needed to find out new techniques for enhancement of data accessing with maintaining security as well as privacy. The solution for this problem is to make the combination of the IoT with block chain which gives a guarantee to sense data integrity. Integration of IoT and block chain resulted in immutable log, comprehensive and easy access. Here, this paper carried out the study of integration of IoT and block chain in relation with different issues, opportunities and application area.