Connacht centre Darragh Leader scored a hat-trick of tries after winger Matt Healy crossed early on for the Westerners but it was to no avail as Munster A secured their third win over the Eagles in three Interprovincial clashes this season.
Connacht made a dream start when Healy darted through a gap in the Munster defence before touching down in the left corner with out-half Miah Nikora off-target with the conversion.
Johnny Holland hit back with the first penalty of the game after a Connacht offside to make it 5-3 to the visitors after eight minutes.
Leader crossed for his first try in the 22nd minute when Connacht exploited an overlap on the left wing and this time Nikora's conversion sailed through the posts and Connacht had a healthy 12-3 lead.
Munster hit back with their first try just three minutes later when Ronan O'Mahony finished well in the right corner after a great break by Luke O'Dea. Holland was off-target with the difficult conversion but the Connacht lead was cut to four.
Munster A took the lead for the first time just after the half hour when Cian Bohane powered over from short-range with Holland adding the easy conversion to give Munster A a 15-12 half-time lead.
The game produced another four tries in the second half with Munster A captain Barry O'Mahony scoring the first after 49 minutes when he pounced on a mistake in the Connacht midfield before showing great pace to outsprint the retreating defence and touch down. Holland once again added the conversion and Munster led 22-12.
It took just three minutes for Connacht to respond as Leader scored his second try with Jack Carty landing the conversion to reduce the Munster lead to just three.
Barry O'Mahony scored his second try with Rory Scannell converting as the game entered the final 20 minutes but the visitors responded immediately yet again with Leader completing his hat-trick and Carty landing a superb touchline conversion.
Scannell put some daylight between the sides with his first penalty on 70 minutes and the Munster A defence held strong for the final ten minutes to secure an excellent win.
Next up for Munster A is the crucial B&I Cup quarter-final in Donnybrook four weeks from today.