Cloud Computing is a model whereby users share data and digital resources through the Internet. Cloud Computing has more scalability, availability and reliability than traditional ways of sharing information. Furthermore, it has more efficiency and less operational cost, thus it would be of great economical importance for all kinds of business especially the small and medium ones. On the other hand, as any technology has pros and cons, Cloud Computing has some obstacles and issues where security in one of the main problems that Cloud Computing is facing. This research deals with a design of a secure framework for Oman Cloud Computing and measures the Advanced Persistent Threat (APT). APT is one of the most sophisticated types of attacks where it targets high-value organizations such as military, finance, government sectors, power sectors, etc. Its main objective is to extract users' credentials rather than destroys the data or network resources such as servers, firewalls, routers and switches. Therefore, study and analysis of APT is very important because it helps to improve Cloud Computing services with less security risks and challenges. In particular, this research is going to find the main factors and measures the effect of an APT attack. Then, it classifies these factors into groups in order to simplify the design of a framework. Furthermore, a survey has been conducted based on the identified factors. In addition, mathematical equations are included for calculating the collected data from the survey to derive the solution. To implement the proposed idea, as SPSS package has also been used for finding the reliability and inter- correlation between various factors, Finally, the APT readiness degree has been analyzed and implemented.