The Sweden international scored between an Ezequiel Lavezzi effort and a Gary Kagelmacher own goal to send PSG eight points clear at the summit ahead of Monaco's trip to Bastia on Saturday.
Ibrahimovic was pleased to see PSG extend their unbeaten league run to nine games, even if Laurent Blanc's men failed to find top gear.
"It was important to win," he told the club's official website. "We did not play our best game but we took the three points.
"If we continue, we will reach our goal at the end of the season."
Yohan Cabaye started his first PSG game at the Parc des Princes on Friday following his move from Newcastle United in January.
"It was important to negotiate the match against Valenciennes before looking towards Leverkusen," he said.
"We will recover and prepare well. It feels good to play a game, it went well."
