A two-fold interpenetrated microporous bi-pillared-layer framework of Fe(II), {[Fe(2,6-napdc)(4,4'-bipy)](EtOH)(H₂O)}$_n$ (1) (2,6-napdc =2,6-naphthalenedicarboxylate; 4,4'-bipy=4,4'-bipyridine) composed of mixed ligand system has been synthesized and structurally characterized. The 2,6-napdc linkers form a 2D corrugated sheet of {Fe(2,6-napdc)}$_n$ by linking the secondary building unit of Fe₂(CO₂)₂ in the $ac$ plane, which are further connected by double 4,4'-bipy pillars resulting in a bi-pillared-layer type 3D framework. The 3D framework is two-fold interpenetrated and exhibits a 3D channel structure ($4.0 \times 3.5, 1.5 \times 0.5$ and $2.2 \times 2.1$ Ų) occupied by the guest water and ethanol molecules. Framework 1 shows high thermal stability, and the desolvated framework (1′) renders permanent porosity realized by N₂ adsorption profile at 77K (BET surface area of $\tilde 52$ m² g^-1). Moreover, the framework 1′ also uptakes different solvent vapours (water, methanol and ethanol) and their type-I profile suggest strong interaction with pore surfaces and overall hydrophilic nature of the framework. Temperature dependent magnetic measurements suggest overall antiferromagnetic behaviour in compound 1.