The first spectroscopic observation of YbS has been made using visible laser excitation spectroscopy. Gas-phase YbS was produced in a Broida oven by the reaction of Yb metal vapour with either CS2 or OCS. Dispersed fluorescence spectra of an Ohm = 0-Ohm = 0 electronic transition were recorded with a CCD array detector. A least-squares fit of 34 band-heads leads to the following molecular parameters for the lower state: omega(e)" = 365.6(1) cm(-1) and omega(e)" x(e)" = 1.14(2) cm(-1). Determination of the parameters for the upper state of the transition was precluded by the irregular vibrational spacings, which increased with increasing upsilon'.