The 41-year old boss has called for the Bhoys to forget about the events surrounding rivals Rangers and focus on retaining their SPL title this term
The Celtic Park outfit have watched their fierce neighbours have their newco application to join the Scottish Premier League rejected, with the Hoops one of the sides to vote against the bid.
Lennon now wants the club to put the event behind them and concentrate on their own future, as they look to enter a new campaign without the prospect of Old Firm derbies.
The 41-year-old told the club's official website: "We cannot let outside negative influences dictate the mood at Celtic, we are very optimistic and we are very much looking forward to the season but we need our fans right with us.
"We are now looking forward and not back, we have a vibrant young team, I want to progress this team as far as I can but we cannot do this without the fans' support.
"We must now move on, and move on with a collective unity between the supporters and the club and the team. We enjoyed that unity last season and we now need this to continue more than ever."
With the exclusion of Rangers from the SPL, the impact could be felt on the Celtic's own income, but Lennon has urged fans to continue supporting and investing in the club.
Lennon added: "We now know what the situation is and where we are and it is a situation we must now deal with.
"We will need the supporters to be right behind the team. We want as many fans as possible to come back to the club and take their seat at Celtic Park and invest in the club as much as possible.
"We need to stand strong, shoulder to shoulder and all work together to continue to move the club in the right direction."