Reale fired a beautiful 63 at Is Molas to share the lead with Englands Mark Roe at 9-under-par.
The local resident made seven birdies and eagled the 464-yard par-4 4th (his 13th hole of the day) when his 7-iron found the bottom of the cup.
Sitting precariously at 207th on the official money list, the 30-year-old essentially needs to win this week to retain his European Tour playing privileges next year.
He explained his situation following the round.
This year I have not played well, said Reale, who has made only nine cuts during the season. I have had a big problem with a tendon in my right arm and maybe in December I will have an operation. Its been a problem for four or five years.
It didnt appear much of a problem on Thursday, as the hometown player is looking to become the first Italian winner on home soil since 1980.
Roe, too, is also in danger of losing his card for 2002.
At 131st on the Order of Merit, he is just over the cutoff point, but is resolved nonetheless to stay on tour.
Theres nothing at stake for me really, claimed Roe following his round of 63. Im not worried about the situation I am in. Other people seem more worried about it than I am.
Ive been out here 17 years. Ive made a decision I am not going to go back to the Tour School whatever happens, and next year I will play what few events I get off my ranking and maybe ask for a few invitations.
Not far behind the duo was Swedens Fredrik Andersson, who rattled in a 7-under 65 Thursday, while three shots back were Anthony Wall, Eduardo Romero and Raymond Russell, all of whom shot 66s.
Meanwhile, defending champion Ian Poulter carded an opening-round 67 to end in joint-ninth with six others.
The young Englishman ' who won Rookie of the Year honors in 2001 ' was happy, but not overjoyed with his game on Day 1.
It could have been very low, he said. It was all out there. Im not over-happy, but 5-under is okay, and it will definitely get better.
As an early lightening storm suspended play for an hour on Thursday, 15 players did not finish their rounds. They will conclude early Friday morning, with the second round commencing thereafter.
Full-Field Scores from the Atlanet Italian Open.