Inhibition mechanisms of staurosporine and H7 to cAMP-dependent protein kinase have been investigated through docking studies. For each molecule, the energetically most stable docking model was searched by using the conformationally flexible automatic docking program ADAM without any presumptions. The results explain well the observation that staurosporine does not bind to the enzyme competitively with H7, even though the two compounds competitively inhibit ATP binding.