In [11], Bayram Sahin established a sharp inequality for warped product skew CR-submanifolds in a Kaehler manifold. In the present paper, we introduce warped product skew CR-submanifolds in cosymplectic manifolds and obtain a sharp inequality between the squared norm of the second fundamental form and the warping function for such submanifolds isometrically immersed in cosymplectic manifolds. The equality case is also considered. © 2012 Pleiades Publishing, Ltd.