Disclosed is a process for the preparation of creatine or creatine monohydrate, wherein cyanamide is reacted with sodium or potassium sarcosinate in water or in a mixture of water and en organic solvent at a temperature of from 20 to 150° C. and a pH value of from 7.0 to 14.0. By means of the process according to the present invention, creatine or creatine monohydrate can be prepared in good yields of from 60 to 90% by weight and with very high purity.
