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Non-orthogonal multiple access (NOMA) scheme has gained attention for its potential to boost spectral efficiency in fifth-generation (5G) and future wireless networks. Other schemes, e.g., multiple-input multiple-output (MIMO) and hybrid automatic repeat request (HARQ), also have been proposed to enhance the performance of such networks. This paper presents a new approach for studying the performance of NOMA scheme combined with MIMO and HARQ in 5G networks. The study focuses on calculating the outage probability (OP) and the expected number of retransmissions. Despite the complexity of analyzing such combination, this study fills a critical gap, as no prior work has addressed this combination using a Markov-based framework. Our findings underscore the method’s simplicity, accuracy, and computational efficiency, and simulations further confirm its validity.