A first-half Justin Richards penalty ensured Kidderminster progressed to the second round of the FA Cup at the expense of Blue Square Premier rivals Cambridge.
Kidderminster bossed the first half with the front pair of Matthew Barnes-Homer and Richards a constant menace to the U's defence.
The Harriers` front pair got their reward in the 17th minute as U's defender Wayne Hatswell wrestled Richards to the ground in the box and the striker stepped up to slot the resulting penalty beyond Danny Potter.
The visitors lacked any cutting edge in the final third with Phil Bolland glancing a header over the bar in the 34th minute in their only meaningful attack.
Cambridge opened the second half as the more lively side and with the Harriers defence looking shaky, substitute Felino Jardim found space 20 yards from goal only for the upright to deny him an equaliser.
Kidderminster goalkeeper Adam Bartlett was called into action moments later, tipping another Bolland header over the bar as the U's built pressure.
Cambridge dominated the middle of the park for much of the second half and looked certain to level twice only for Bartlett to deny Mark Beesley on both occasions.