We report the results of a search for a W′ boson produced in pp¯ collisions at a center-of-mass energy of 1.8 TeV using a 107pb−1 data sample recorded by the Collider Detector at Fermilab. We consider the decay channel W′→μνμ and search for anomalous production of high transverse mass μνμ lepton pairs. We observe no excess of events above background and set limits on the rate of W′ boson production and decay relative to standard model W boson production and decay using a fit of the transverse mass distribution observed. If we assume standard model strength couplings of the W′ boson to quark and lepton pairs, we exclude a W′ boson with invariant mass less than 660GeV/c2 at 95% confidence level.