  We present the synthesis and a detail investigation of structural and
magnetic properties of polycrystalline [VO(HCOO)$_2\cdot$(H$_2$O)] by means of
x-ray diffraction, magnetic susceptibility, high-field magnetization, heat
capacity, and electron spin resonance measurements. It crystallizes in a
orthorhombic structure with space group $Pcca$. It features distorted VO$_6$
octahedra connected via HCOO linker (formate anions) forming a two-dimensional
square lattice network with a bilayered structure. Analysis of magnetic
susceptibility, high field magnetization, and heat capacity data in terms of
the frustrated square lattice model unambiguously establish
quasi-two-dimensional nature of the compound with nearest neighbour interaction
$J_1/k_{\rm B} \simeq 11.7$~K and next-nearest-neighbour interaction
$J_2/k_{\rm B} \simeq 0.02$~K. It undergoes a N\'eel antiferromagnetic ordering
at $T_{\rm N} \simeq 1.1$~K. The ratio $\theta_{\rm CW}/T_{\rm N} \simeq 10.9$
reflects excellent two-dimensionality of the spin-lattice in the compound. A
strong in-plane anisotropy is inferred from the linear increase of $T_{\rm N}$
with magnetic field, consistent with the structural data.
