The crystal structure of the title compound, C(10)H(13)NO(4), features inter-molecular O-H⋯O(nitro) hydrogen bonding, which links mol-ecules into supra-molecular chains running parallel to the bc diagonal. There is also π-π stacking between 4-nitro-phenyl groups, the inter-planar distance between the nitro-benzene rings being 3.472 (2) Å.