Memristor coupled neurons have complex nonlinear dynamic behavior and have been widely used in neural computing and chaotic systems. In this paper, a new magnetic controlled memristor model is proposed, and the Hindmarsh-Rose(HR) neuron model is established. The neural model is analyzed by bifurcating diagram, Lyapunov exponent spectrum, phase diagram and time series diagram. Then the chaotic sequence generated by the model is applied to the DNA chaotic image encryption algorithm. The experimental results show that this HR neuron model can generate multiple discharge modes and complex chaotic behavior under the influence of magnetic induction intensity, and the generated chaotic sequences based on the model have the characteristics of randomness, initial value sensitivity, ergodic, etc., which has strong security when applied to chaotic image encryption algorithms. These results will provide strong support for understanding the dynamics of neuron hiding and constructing memristor neural network, and have great application value for the treatment of neuron-related lesions.