Concerning on the smart city construction，the big data with cloud computing would serve the key questions related to personal privacy protection and data security which is produced，stored and analyzed in various forms of business sales，personal consumption habits，identity and so forth released by the Internet in the new era. Taking the information leak and cryptographic techniques event of Education and Research Network as an example，against the usage of cloud computing，application development interface，malicious insiders preparedness，the cutting-edge technology of cloud computing data security and privacy protection is investigated to provide suggestions and countermeasures for innovative smart city building，strategic resource planning and personal privacy protective measures. As a result，enhancing the safety awareness of personal privacy protection would promote security management and monitoring services of cloud computing，as well as the innovative development of e-commerce.