The Argentina international had to be substituted at half-time during last week's Champions League quarter-final first leg at Parc de Princes after picking up a hamstring injury.
Messi was unable to play any part in Barcelona's 5-0 league win over Real Mallorca at the weekend but Roura is hopeful the star forward, who scored the opener in last week's 2-2 in Paris, will feature in the return at the Nou Camp.
"We hope he'll be able to play," Roura told a press conference.
"He is reacting well but we will have to wait a while before we know how he feels and what the doctors' tests say."
Roura warned, however, that the club are not prepared to take any risks with Messi, who has scored eight goals in eight starts in the Champions League season.
"I've said before that if a player plays it is because it has been guaranteed that he is capable of playing. We will see what happens, there is still a bit of time left," he said.
Barcelona were leading 2-1 in the first leg until they conceded an equaliser in injury time, and Roura did not hide his disappointment about the result.
Barca can qualify for the semi-finals by drawing the second leg in the Nou Camp either 0-0 or 1-1, but Roura promised his side would go looking for victory.
"Not winning in France left a bad taste in our mouths, but we have to go out and win the match, as if it were a final," he said.
"We won't speculate and we'll go out to win the game from the start. Then, according to how the game turns out, we'll see what we do."
Midfielder Andres Iniesta defended Messi's prominent role in the side, but emphasised that the team can cope without him - as demonstrated by their weekend demolition of Mallorca.
Asked by reporters if the Catalans suffer from 'Messi-dependence', Iniesta said: "Without a doubt, we depend on Messi in the sense that he is a fundamental player for us. When he plays, he's our number one player.
"But we aren't dependent on Messi - he benefits from the way in which the team plays.
"Of course, it's different when he's not playing, but we have a squad and everyone that is in that squad can play and perform to the highest level."
Barcelona are bidding to reach their sixth consecutive Champions League semi-final.
They were eliminated at the last-four stage by Chelsea last year, and Iniesta is keen to avoid a repeat.
He said: "Sometimes we play well, other times we don't.
"What we don't lack is the ambition to get into the semi-finals and to then try and get into the final, which eluded us last year.
"I'm confident that we can continue to be successful."