The title compound, [La2(H2O)4(C7H3N2O6)6]n(I), synthesized by the hydrothermal reaction of 3,5-dinitrobenzoic acid and 1,10-phenanthroline with La(ClO4)3· 6H2O crystallizes in the triclinic system, space group P $$\bar 1$$ with a= 9.566(2) Å, b= 12.126(3) Å, c= 14.214(3) Å, α = 114.614(3)°, β = 103.246(3)°, γ = 97.130(3)°, V= 1413.3(6) Å3, Z= 2, R(F) = 0.0392 and wR(F2) = 0.0425. In I, each La3+ion is coordinated by six oxygen atoms of six carboxylate ligands and two oxygen atoms of two coordinated water molecules. The 3,5-dinitrobenzoato anions bridge the La(III) centers to form one-dimensional linear chains, and π–π interaction between the phenyl rings of 3,5-dinitrobenzoato anions of adjacent linear chains links the chains to engender a two-dimensional network.