The WWγ gauge boson couplings were measured using p¯p→ℓνγ+X ( ℓ=e,μ) events at √s=1.8 TeV observed with the D0 detector at the Fermilab Tevatron Collider. The signal, obtained from the data corresponding to an integrated luminosity of 13.8pb−1, agrees well with the standard model prediction. A fit to the photon transverse energy spectrum yields limits at the 95% confidence level on the CP-conserving anomalous coupling parameters of −1.6<Δκ<1.8 ( λ=0) and −0.6<λ<0.6 ( Δκ=0). Similar limits are obtained for the CP-violating coupling parameters.Received 11 May 1995DOI:https://doi.org/10.1103/PhysRevLett.75.1034©1995 American Physical Society