Aims. We searched for massive stars with Balmer emission consistent with magnetically confined circumstellar material.Methods. Archival spectroscopic and photometric data were investigated.Results. HR 7355 is a formerly unknown He-strong star showing Balmer emission. At mag, it is one of the brightest objects simultaneously showing anomalous helium absorption and hydrogen emission. Among similar objects, only Ori E has so far been subjected to any systematic analysis of the circumstellar material responsible for the emission. We argue that the double-wave photometric period of 0.52 d corresponds to the rotation period. In tandem with the high projected equatorial velocity, sin = 320 km s, this short period suggests that HR 7355 is the most rapidly rotating He-strong star known to date; a class that was hitherto expected to host stars with slow to moderate rotation only. © 2008 ESO.