Healthcare applications are widely used by physicians, patients, and the public to update their health status dynamically. Many sensors are used in healthcare applications for collecting input data from end users and it needs to be maintained as sensitive data. The sensitive data needs to be saved safely in network servers. The various attackers are trying to misuse the data. To handle the attackers, people have started using blockchain technology to secure the data effectively by detecting the attackers. This paper proposes a new secured data transmission system called Blockchain Technology that incorporates a Simple Fuzzy Neural Network (BSFNN) using blockchain technology and a simple fuzzy neural network (SFNN) to securely share healthcare data by patients, physicians, and other medical professionals. Here, the blockchain technology incorporates the Caesar Cipher and Elliptic-Curve Cryptography Diffie–Hellman (EC(DH)2) for securing the data. Moreover, an SFNN is used for detecting the attackers by analyzing the users. The proposed system is tested through experimental results and also proved that the proposed system is superior to other systems with respect to security level, communication time, encryption time, and decryption time.