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In this manuscript, a cooperative non-orthogonal multiple access based intelli-gent mobile edge computing (NOMA-MEC) communication system is constructed in detail. The nearby user is viewed as a decoding and forwarding relay, which can assist a distant user in offloading tasks to the intelligent MEC server. Then, the closed-form expressions of offloading outage probability for a pair of us-ers are derived in detail to evaluate the perfor-mance of the cooperative NOMA-MEC sys-tem. Furthermore, the approximate expressions of offloading outage probability are provided in the high signal-to-noise ratio region. Based on the asymptotic analyses, the diversity order of distant user and nearby user is n+m+1 and n+1, respectively. The system throughput and energy efficiency of cooperative NOMA-MEC are analyzed in delay-limited transmission mode. Numerical results show that 1) Cooper-ative NOMA-MEC is better than orthogonal multiple access (OMA) in terms of offload performance; 2) The offload performance of cooperative NOMA-MEC system improves as the number of transmission task decreases; and 3) Cooperative NOMA-MEC performs better than OMA in energy efficiency.