The present invention relates to a process for the preparation of pharmaceutically acceptable salts of (R,S)-S-adenosyl-L-methionine and allows to obtain the salified (R)-(+)-S-adenosyl-L-methionine diasteroisomer in amounts lower than or equal to 3% with respect to the salified (S)-(+)-S-adenosyl-L-methionine diastereoisomer; the salts that can be obtained by the process of the invention keep their configuration stable in time.