The wetting behavior of aqueous solutions of two types of siloxane surfactant (dicephalic and gemini) on two hydrophobic substrates was investigated. Solutions of dicephalic surfactant demonstrate rapid and complete wetting on Parifilm surface and only partial wetting on Teflon. An increase in surfactant concentration results in a transition from partial to complete wetting. The solutions of gemini surfactant show only partial wetting on both Teflon and Parifilm. It is demonstrated that wetting behavior depends crucially on surfactant structure; substrate surface affects the wetting behavior of siloxane surfactant.