Wednesday had dominated the opening half with Marcus Tudgay hitting the woodwork before Ipswich sparked into life but they could find no way past the Owls keeper.
Former Hillsborough midfielder Alan Quinn, who spent seven years with the South Yorkshire side, was foiled by Lee Grant, who pulled of two stunning saves late in the game as Wednesday fell apart.
Wednesday started brightly and almost snatched the lead in the eighth minute. Jermaine Johnson picked out Tudgay whose stinging 25-yard drive cracked against the bar with Richard Wright beaten.
Ipswich survived after centre-back Richard Naylor gave away a free-kick on the edge of the area, midfielder Etienne Esajas found Tudgay whose diving header flashed inches over the target.
The Portman Road side squandered a chance as the Sheffield defence backed off. David Norris unselfishly passed inside to ex-Sheffield United striker Jon Stead, but the £600,000 signing casually side-footed over from ten yards.
Wednesday dominated but still failed to cash in on some frail defending, Steve Watson charged from midfield, cleverly evading two tackles, but his 15-yard shot lacked power with Wright snatching the ball on the line.
Quinn ignored the barracking from the Hillsborough fans as he drilled in a low right-foot strike from 22 yards, the ball flashing a fraction wide of the far post beyond the diving Grant.
Ipswich were in trouble again failing to cut out Dutchman Esajas' teasing corner from the left. Johnson was the quickest to react stretching to meet the ball but he powered the ball straight to the Ipswich keeper.
Midfielder Johnson, partnering Tudgay up front with the Hillsborough side short of strikers, was too quick for the Ipswich back four as he cut inside from the right flank with the alert Wright smothering the ball on the line.
Quinn, who also spent four years at city rivals Sheffield United, caused havoc as Ipswich came out after the break in more determined mood.
The former Republic of Ireland international cleverly steered his right-foot shot towards the far corner but the unsighted Grant managed to palm the ball away before grabbing it at the second attempt.
The Wednesday keeper, unemployed for much of the game, pulled off another save in the 65th minute, after the Sheffield side failed to stop Jonathan Walters, the striker drilling in a low shot that was scooped up by Grant.
The Sheffield side escaped ten minutes from the end as Ipswich grew in confidence, the hard-working Norris weaving his way into the area before finishing with a left-foot shot , the ball bouncing off the bar into Grant's hands.
Grant foiled Norris again diving bravely at the midfielder's feet after Wednesday had failed to cut out substitute Kevin Lisbie's back header to set up a nail-biting finish.