—Spin-torque transfer magnetic random access memory (STT-MRAM) has emerged as a promising non-volatile memory technology, with advantages such asscalability, speed, endurance and power consumption. This paper presents a STT-MRAM cell operation channel model with write and read operations for information theorists and error correction code designers. This model takes into account the effects of process variations and thermal fluctuations and considers all principle flaws during the fabrication and operation processes.With this model, evaluations are not only made for the write channel, the read channel, but alsothe write and read channel with metricssuch as operation failure rate, bit error rate, channel ergodiccapacity and channel outage probability at certain outage capacity. Moreover, it is proved that the distributions of written-in bit states are not uniformly distributed andare proportional to their respective write success probabilities. Finally, simulation results show that practical code rates and code block lengths can guarantee reliable performances only if the operation success rate difference between state '1' and state '0'is small enough. Index Terms—Spin-Torque Transfer Magnetic Random Access Memory (STT-MRAM), Non-Volatile Memory (NVM), Error Correction Code (ECC), Write Operation, Read Operation, Channel Model, Operation Failure Rate, Bit ErrorRate (BER), Channel Ergodic Capacity, Channel Outage Capacity, Channel Outage Probability.