The Health Information Technology for Economic and clinical Health (HITECH) Act of 2009 encourages the use of Electronic Health Records. EHR improves the data accessibility, ease thecomputerized data updation and allows e-messaging between providers. Cloud computing offers various services to health care units, the data are stored in the cloud. Three important aspects of cloud is performance, availability and security.Hence, there is the need for efficient homomrphic crypto algorithms. This paper propses the efficient homomorphic encryption algorithm to encrypt the medical images and to perform useful operations on them without breaking the confidentiality.