The experienced forward, who has netted 13 times this season, missed Orient's 2-1 loss at Rotherham United at the weekend.
A groin problem has troubled the veteran in recent weeks, but Slade is confident that Lisbie will be fit to take part against Peterborough.
"He's had a little injection in his groin but he will be fine," Slade told reporters at a press conference.
"There are one or two other bumps and bruises but we've got good characters and we need to bounce back on Saturday."
Orient currently sit third in League One, three points from leaders Brentford.