We construct one-way function based on a finite ring. One-way function in this paper means that to find the inverse of the function is hard computationally. We have used the extension of group action to construct this function and applied it to encipher the given plain text. To decipher the enciphered text generated by this function is considerded a hard problem. but not impossible theoretically. However, a successful enciphering system. for example, RSA system which depends on the difficulty of factoring, need not have mathematically perfectness.