The present work is an experimental study of the mass transfer characteristics of a swirling jet impinging on a flat plate. The main objective of the investigation was to determine the influence of a circumferential velocity component (the swirl component) on the local and average mass transfer coefficients at the plate surface. The dimensionless parameters investigated were the jet Reynolds number, the jet-to-plate distance, and the strength of the swirl flow given by the swirl number. Mass transfer coefficients were obtained utilizing the naphthalene sublimation technique. The local coefficients were determined employing a computerized coodinate table which allowed a detailed study of the effects of the presence of the swirl component. Average coefficients were determined independently through precision weighing, and displayed excellent agreement with the integrated local coefficients. The results demonstrated that the presence of the swirl component decreases the mass transfer coefficients, when compared with the non-swirl case. Flow visualization experiments were conducted utilizing the oil-lamp black technique. The results revealed regions of reverse flow at the stagnation zone for high values of the swirl number.