Palmitoylated Wnt proteins comprise a conserved family of secreted signaling molecules associated with variety of human cancers. WIF domain of the human WIF (Wnt inhibitory factor)-1 is sufficient for Wnt binding and signaling inhibition. Detailed interactions between Wnt and WIF-1 are not known. Computational docking was employed to identify a possible fatty acid binding site in the WIF domain. A putative binding site was identified inside the domain. WIF domain exhibited the highest affinity for C160-C180 (-22 kJ/mol free energy of binding) fatty acids. The results suggest a role of the WIF domain as a palmitoyl binding domain required for WIF-1 binding to palmitoylated Wnt and signaling inhibition.