The rapid advancement of cloud computing has significantly transformed healthcare information managementbyenabling secure storage, efficient processing, and seamless sharing of electronic health records across geographicallydistributedhealthcare organizations. Smart healthcare applications continuously generate large volumes of sensitive medical informationthrough electronic health records, wearable devices, wireless body area networks, remote patient monitoring systems, andhospitalinformation systems. Ensuring the confidentiality, integrity, availability, and secure exchange of healthcare informationremainsamajor challenge due to increasing cybersecurity threats, unauthorized access, data breaches, and privacy concerns. Thisexperimental study proposes a secure data sharing framework for smart healthcare applications using cloud computingthatintegrates secure cloud infrastructure, authentication mechanisms, access control policies, encryption techniques, andprivacy-preserving data management into a unified architecture. The proposed framework evaluates system security, dataaccessibility,computational efficiency, resource utilization, communication reliability, and Quality of Service within cloud-enabledhealthcareenvironments. A mathematical framework and algorithmic strategy are developed to measure secure data transmission, accesscontrol effectiveness, privacy preservation, and healthcare information availability. Experimental evaluation demonstratesthattheproposed cloud-based framework significantly improves secure healthcare data sharing while reducing communicationoverhead,strengthening privacy protection, and enhancing system scalability and reliability. The proposed framework provides valuableguidance for researchers, healthcare organizations, and cloud service providers seeking to design secure, efficient, andscalablecloud-enabled smart healthcare systems. Keywords: Secure Data Sharing, Smart Healthcare, Cloud Computing, Electronic Health Records, Healthcare InformationSecurity.