The disclosure relates to a process for the preparation of the enantiomeric forms of 2,3-diaminopropionic acid derivatives of formula I, wherein R1, R2 and R3 are defined as in the disclosure, by racemate resolution. The separation of the racemate into its enantiomers takes place through formation of diastereomeric salts upon addition of an enantiomerically pure auxiliary, and subsequent separation by fractional crystallization.