Abstract: The present invention provides an imidazopyridine compound represented by formula (I), wherein R1 and R2 each independently represent a C1-6 alkyl group et al; R3 and R4 each independently represent a hydrogen atom, a methyl et al; Ar1 is a divalent substituent representing a monocyclic or bicyclic, 3- to 8-membered aromatic or aliphatic heterocyclic group et al; Ar2 represents an aromatic carbocyclic group, or an aromatic heterocyclic group; W represents —(CH2)m et al, and m indicates an integer of from 0 to 10. This compound acts as a melanin concentrating hormone receptor antagonist, and is useful as treating agents for obesity.