Abstract: The COVID-19 (Corona Virus) is an intensely rising virus that has intentioned countries to utilize technologies to identify Covid disease. Several countries are working incredibly to battle against COVID-19. Numerous countries have been utilizing a range of gadgets to contest the pandemic, looking for data about growth, perceiving as well as the emancipating the personal data of the inhabitants. In the present situation of COVID-19 (Corona Virus) legislative institutes all around the world make an effort to build a monitoring system that notifies about declared cases throughout the world. Several Researcher suggested IoT and Blockchain-based applications for this reason. The significant thought behind a IoT and Blockchain-based system for monitoring is quality services, information handling and prevent from Single Point of Failure. Even now , it raises various issues concerning to Security Issues, Legal Disputes, Privacy Requirements, Latency, Throughput, Scalability, Intense Traffic and Block Size. This article aims to discuss these IoT and Blockchain-based applications Challenges.