INTRODUCTION: Most cavernous carotid aneurysms (CCAs) are asymptomatic benign lesions; therefore, they are frequently detected during routine clinical diagnostic processes. Most providers recommend routine surveillance instead of immediate management for CCAs given a natural history with a low risk of life-threatening complications. However, the cost-effectiveness of such care and the optimal follow-up interval remains unknown. METHODS: A decision analysis study was performed utilizing a Markov model with Monte Carlo simulations to simulate patients undergoing treatment or routine surveillance at different time intervals (half, 1-,2-,3-, 5-and 7-year intervals) for different size of CCAs (=<12 mm, 13- 24 mm, >=25 mm ). Input data for the model was extracted from the current literature. Probabilistic and deterministic sensitivity analyses were performed to evaluate the robustness of the Model. RESULTS: On base case analysis, following-up every 2 years with noninvasive imaging is the most cost-effective strategy for CCAs =< 12 mm, while annual follow up is cost-effective for large/giant (13-24 mm, >=25 mm) CCAs. The conclusions remain robust in probabilistic sensitivity and deterministic sensitivity analyses. As the risk of thrombo-embolic event gets higher and annual growth risk and annual rupture risk of CCAs increases, immediate treatment for large/giant (13- 24 mm, >=25 mm ) CCAs and annual follow up even prompt treatment for CCAs =< 12 mm is optimal. CONCLUSIONS: The most cost-effective management strategy for CCAs=< 12 mm and large/giant CCAs are following up every 2 years and following up every year, respectively. More frequent follow-up strategies or prompt preventive treatment for CCAs =< 12 mm and immediate treatment for large/giant CCAs would be more appropriate in patients with higher risk factors for cerebral ischemia, aneurysm growth and aneurysm rupture.