A computer stylus may have an elongated body with a metal tube that serves as an antenna ground for an antenna. An antenna resonating element for the antenna may be formed from metal traces that wrap around a longitudinal axis for the elongated body. The antenna may be an inverted-F antenna. A ground antenna feed terminal for the inverted-F antenna may be coupled to the metal tube with a sheet metal member, conductive fabric, and solder. A clip may run along a side of the elongated body at a location that does not overlap the metal traces of the antenna resonating element. The antenna may be fed at a location on an opposing side of the elongated body from the clip. Antenna signals from the inverted-F antenna may be reflected towards the tip by metal structures at the end of the elongated body opposing the tip.