Nowadays, in the global markets companies have to produce highquality product, low cost product in order to be alived in competetive markets. Group technology helps manufacturer to raech this aim. One of the most proper applications of group technology is called Cellular Manufacturing System (CMS). CMS is able to implement in the manufacturing system for overcoming the waeakness of traditional manufacturing system such as Job shop, Flow shop. One of the main challenging issues in CMS is named machine reliability and breakdown. Although, production facilities and machines are improving and becoming more sophisticated, they are not free from deterioration due to the aging which leads to shifting from in-control to out-of-control state for the machines and also breakdown of machines in the planning horizon. This study provides a comprehensive review on literature of machine reliability in cellular manufacturing system. This study made attempts to gather all the researches which have been done on machine reliability in CMS. In fact this issue was considered by the author since, moving from in-control state to out-of-control state and also machine breakdown have effective impacts on the system; therefore, it is essential for manufacturers to consider this subject in their study for preventing the huge wastage of time and cost in the system which will be occurred as results of this phenomena.