In ancient times, humans were much predisposed to utilizing their handcreated tools to finish any kind of work. From the last few years, businesses related to production have been expanding. People began to rely on tools, machines, and smart gadgets to process their work, as these kinds of tools help them to achieve their target in the given time. . Since the 18th century, the world has experienced a lot of revolutions in industry across the globe. This type of growth in technology has made a base for industrial revolutions. New technology was introduced called “blockchain.”Probably, blockchain technology is the most disruptive technology in the modern digital economy. The ability of blockchain technology has been greatly described in many research works, media, and majorly in the fields of finance and payment. One existing research is at the organizational stage, where it implements the architecture for internet safety as well as inconvertibility. “Industry 4.0” and “IIoT (Industrial Internet of Things)” are involved in its rising applications. Thus, in this paper, current applications of blockchain in IIoT as well as Industry 4.0 setups, existing open issues, modern application sectors, challenges related to IIoT, and their solutions are illustrated. The main focus of this paper is to empower and facilitate research in this field, which will help the developers in blockchain acquisition as well as investment in the “Industry 4.0” and “Industrial Internet of Things” space.