In a bright start for the Yeltz, Dan Sweeney's 12th minute low drive was turned around the post by visiting goalkeeper Martin Conway and Sweeney's header was cleared off the line from Joel Taylor's resulting corner.
Taylor then connected well but lashed inches wide of the post after Matt Curley crossed from the right at the end of a neat 20th minute move.
With Halesowen on better form than for some time, Sweeney went even closer when his 26th minute header bounced off the underside of the crossbar and
Conway was able to grab the loose ball after Taylor crossed from the left.
As the home pressure continued to mount, a 36th minute wide-angle shot from Sweeney was beaten away by Conway and Billy Murphy's header was cleared off the line by Ty Ward a minute later.
An excellent 40th minute move then saw Taylor set Sweeney free but Conway made another fine save with his legs as St Ives gave stubborn resistance.
But St Ives stunned the Yeltz by stealing a 42nd minute sucker-punch lead with their first and only chance of the game against the run of play.
Jake Newman spotted goalkeeper Dan Platt off his line and his speculative 35 yard chip bounced over Platt into the top corner of the net.
The one-way traffic continued in the second half with St Ives mounting a solid rearguard action.
Visiting centre half Jarvis Wilson hooked off the line from Curley's 56th minute looping header and Sweeney nodded straight at
Conway two minutes later. After a further two corners, Curley fired wide after 67 minutes as Halesowen tried to be patient to find a way back into the game.
An 83rd minute Yeltz corner then resulted in a goalmouth scramble, but once again St Ives put bodies behind the ball to clear.
Just as it looked like St Ives would complete their smash and grab raid, Halesowen finally found a deserved equaliser in the sixth minute of added time as Taylor burst into the box down the left and was brought down.
Home substitute Hughes stroked home the resulting penalty after St Ives' Charlie De'ath received a red card for his second bookable offence.
Halesowen Town: Dan Platt; Matt Curley (Aaron Gilpin 80), Jack Kelly, Sam Griffiths, Kieran Morris, William Murphy, Jack Rea (c), Callum Coyle (Lee Hughes 72), Andre Wright, Dan Sweeney, Joel Taylor.
Subs Not Used: Joe Fitzpatrick, Danny Bragoli, Dominic Hill.
St Ives Town: Martin Conway; Ben Jackson, Mark Coulson (Ben Toseland 75), Taona Sundire, Jarvis Wilson, Charlie De'ath, Ben Baker (Danny Kelly 59), Robert Parker (c), Jake Newman, Ty Ward, Oliver Snaith (Andrew Osei-Bonsu 65).
Subs Not Used: Benjamin Seymour-Shove, George Bailey.
Referee: Ben Cooke Attendance: 363