Absorption cross-sections of the vinyl radical (C 2 H 3 ) have been determined in the spectral range 440-460 nm, using laser photolysis coupled with a cavity ring-down spectroscopic detection technique. The disappearance rate of vinyl radical by its absorption in A 2 A''-X 2 A' transition was probed by visible cavity ring-down spectroscopy. Based on a reaction kinetics simulation, the absorption cross-sections of the vinyl radical were estimated.