Abstract: In a method for efficiently inducing reprogramming of human cells into neuronal cells, a concentration of cAMP is increased or an expression of PKA and CREB is up-regulated or an expression of AMPK, ALK2, ALK3, P38, and JNK is inhibited by a single small molecule compound or gene knockout or gene overexpression. In the present disclosure, the induction small molecule compound is single and safe, and has a short induction time, high induction efficiency, definite induction sites and genes, and clear molecular regulation mechanism. The small molecule compound can be applied to the clinical treatment of human neurodegenerative diseases, providing a safer and more efficient treatment method for the neurodegenerative diseases. Since neuronal cells cannot divide and proliferate, the method induces fibroblasts and astrocytes that can divide and proliferate in vitro and in vivo, to continuously obtain a large number of induced neuronal cells in vitro and in vivo.