This present invention provides a method for continuously maintaining growth of a motor neuron progenitor cell and a pharmaceutical composition. Wherein, the method for continuously maintaining growth of a motor neuron progenitor cell is to culture the motor neuron progenitor cell in an environment which is constructed by the olfactory ensheathing cells to make the motor neuron progenitor cell sustain the ability to self-replicate and to be induced for differentiating into mature neuron, and therefore to elaborate the effect to protect the motor neuron. The motor neuron progenitor cell produced from the method disclosed in this present invention can be an effective ingredient of the pharmaceutical composition for treating related diseases of damaged motor neuron.
