Two first uranyl chromate nitrates, K[(UO ₂)(CrO ₄)(NO ₃)] (1) and Rb[(UO ₂)(CrO ₄)(NO ₃)] (2), were prepared by solid-state reactions and characterized by electron microprobe analysis and single-crystal X-ray diffraction. The compounds are isotypic [1: monoclinic, P2 ₁/c, a = 9.881(5), b = 7.215(4), c = 14.226(6) Å, β = 124.85(3)°, V = 832.3(7) Å ³; 2: monoclinic, P2 ₁/c, a = 9.804(1), b = 7.359(1), c = 14.269(1) Å, β = 122.048(4), V = 872.6(1) Å ³]. The structures of 1 and 2 are based upon the complex [(UO ₂)(CrO ₄)(NO ₃)] ^- layers with unprecedented structural topology, which consist of the UrO ₃NO ₃ units linked through CrO ₄ tetrahedra. The resulted kinked layer can be divided into chains arranged in the ladder fashion. The layers are parallel to (100) and are linked by A ⁺ (A = K, Rb) cations located between the layers.