Competing at the Prosper Golf Resort in Celadna, Lawrie did not drop a shot en route carding a six-under-par round of 66 to ensure he will head the field going into today's second round of the event.
Starting at the 10th hole, Lawrie conjured up birdies in three of the last five - the fifth, sixth and eighth on the course - to make himself the early leader.
Lawrie told The Irish Times: "I played lovely golf today," he said. "No bogeys, which always helps. A couple of nice up-and-downs when I really needed them - on two and three - my 11th and 12th. Other than that, I played lovely, solid golf, and every chance I gave myself from short range, I holed it - though I missed about a ten footer at the last."
The 37-year-old Dubliner, runner-up at this event last year, was followed by countrymen Damien McGrane and Shane Lowry with rounds of 67 and 68 respectively, both only dropping one shot.
Lowry's highlight, in particular, was an eagle at the 576-yard, par-five fifth hole, the 14th of his round after also starting at the 10th.
Lowry said: "Since I had a good finish at Wentworth I haven't really done too much, and that's purely down to my putting, because I've been playing quite nicely from tee to green. When you're not putting well, it tends to affect the rest of your game, because you tend to try to force the issue and attack the pins too much."
McGrane added: "The scoring conditions are perfect, so it's possible to create a lot of chances.
"But creating them is one thing, converting them quite another. So to make six birdies and just the one bogey was very pleasing.
The Irish trio were followed by a group of players on three under that included the Scottish duo Gary Orr and Richie Ramsay.
England's Jamie Elson, Steve Webster and Richard McEvoy, as well as Scotland's Steven O'Hara, are then in a large group of players on two under.
The leading player in the field, Spain's Miguel Angel Jimenez who is world ranked 34, seemingly faces a fight to make the cut after a four-over par round of 76.