Leading the side out were three Ulster stalwarts, with prop, Andy Warwick, and lock, Alan O'Connor, making their 200th Ulster appearances on the night. Nick Timoney also started on what was his 150th game.
The team sported a new look, debuting the new third kit inspired by the province.
Ulster started off on the front foot and took a lead just two minutes into the match, with hooker, John Andrew, going over from the driving lineout maul. John Cooney added the extras from the tee for an early 7-0 lead.
Connacht grew into the game and through penalties got their way into the Ulster 22. The ball was then worked wide to winger Shayne Bolton, who dived over in the left corner for the away side's opening try of the contest. Josh Ioane missed the conversion.
Ulster then received a huge blow around the 15 minute mark when captain Iain Henderson came off for an HIA following a head on head collision. Alan O'Connor came on for his 200th Ulster cap to replace the skipper.
Richie Murphy's side were on the money with their set piece and scored a second try through Jude Postlethwaite after another lineout maul. The young centre, who just returned from the Emerging Ireland tour earlier in the week, picked and drove over the line for an important try.
The rain started to pour down in Belfast and it was clear that both sides were targeting the high balls to force the opposition into knock ons.
Ulster's next try came from an inventive lineout routine, with John Cooney finding space and sprinting through a gap in the Connacht defence. The scrum-half couldn't be caught and he went under the posts for his first try of the season. To add the cherry on top he converted his own score to make it 19-5.
Pete Wilkins side showed their competitiveness with a reply, with lock, Joe Joyce, going over from close range after a lineout on the Ulster 5m line.
Ulster then had to contend with 14 men, after Werner Kok was shown a yellow card for tackling a player in the air.
Just before the break, Connacht's Ben Murphy pounced on a gap in Ulster's defence and after slipping a tackle, the scrum-half notched his fourth try of the season for the away side.
The converted try left it a two point game at 19-17.
HT: 19-17
Connacht looked the more dangerous side directly after the interval, with an early try attempt just minutes in.
Referee, Andrew Brace, had initially awarded a try for the Westerners but a TMO check would confirm that Sean O'Brien had not grounded the ball.
With Ulster returned to 15 players, the home side punished Connacht in next phases.
Lock, Josh Murphy, was shown a yellow card after a series of penalties and Ulster went after the corner and used their lineout maul once again for their bonus-point try, scored by David McCann, who picked and went from close range.
In the back and forth contest, the pendulum then swung towards Connacht, who managed to draw level with Ulster after replacement, Dylan Tierney-Martin, went over from Connacht's lineout maul.
Ioane's converison made the score 24-24 with under twenty minutes left in the game.
With Ulster on the attack, the game took a turn when Josh Murphy was shown a straight red card for a head on, off the ball tackle on replacment hooker, James McCormick.
From the resulting penalty, John Cooney, didn't waste the opportunity to kick Ulster into a narrow lead.
With the game closing to an end, Ulster added the breathing room needed and it was the man making his 150th appearance for his province, Nick Timoney, who muscled over the whitewash from a maul in the Connacht 22.
Josh Ioane's late penalty secured the Westerners a losing bonus point but ended the contest, with Ulster closing out their first interpro derby of the season with a win in front of noisy home support.
The province will now turn their focus to next Friday's Round 5 home clash against Ospreys, hoping to make it three home wins on the bounce.
Scorers
Ulster
TRY: Andrew, Postlethwaite, Cooney, McCann, Timoney
CON: Cooney x2
PEN: Cooney
Connacht:
TRY: Bolton, Joyce, Murphy, Tierney-Martin
CON: Ioane x2
PEN: Ioane
Teams
Ulster
(1-8) Andrew Warwick, John Andrew, Tom O’Toole, Iain Henderson (C), Kieran Treadwell, David McCann, Sean Reffell, Nick Timoney;
(15-9) Ethan McIlroy, Werner Kok, Stewart Moore, Jude Postlethwaite, Jacob Stockdale, Aidan Morgan, John Cooney.
Replacements: James McCormick, Callum Reid, Corrie Barrett, Alan O’Connor, Marcus Rea, Nathan Doak, Ben Carson, Mike Lowry.
Connacht
(15-9) Santiago Cordero; Mack Hansen, Piers O'Conor, Bundee Aki, Shayne Bolton; Josh Ioane, Ben Murphy;
(1-8) Denis Buckley, Dave Heffernan, Finlay Bealham; Joe Joyce, Josh Murphy; Cian Prendergast (C) Sean O’Brien, Paul Boyle.
Replacements: Dylan Tierney-Martin, Peter Dooley, Temi Lasisi, Oisin Dowling, David O’Connor, Caolin Blade, Cathal Forde, Conor Oliver.
