Two enantiomeric counterparts (l- and d-asparginium cations related by glide planes) are present in the structure of the title compound, C4H9N2O3
+·ClO4
−, with a 1:1 cation–anion ratio. The structure is built up from asparginium cations and perchlorate anions. In the crystal, molecules assemble in double layers parallel to (100) through N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds. In the asparginium layers, hydrogen bonds generate alternating R
2
2(8) and R
4
3(18) graph-set motifs. Further hydrogen bonds involving the anions and cations result in the formation of a three-dimensional network