The 12-time champions will face Vietnam in the quarter-finals, having booked their place in the knockout stage with a match to spare.
Iran were left frustrated by Lebanon’s early resistance with the West Asians threatening in the third minute through Fadi Greij’s shot, while at the other end Saeid Ahmad Abbasi did well to control Saeid Momen’s long throw but hit his half-volley high above the bar.
Iran gradually took control with Hossein Tayebibidgoli missing the target from just inside the box before Mohammadhossein Bazyar’s forced effort off a corner was easily collected by Lebanon keeper Karim Joueidi.
Iran finally broke the deadlock in the eighth minute with Salar Aghapour netting a beautiful individual effort, shooting into the top right corner.
Alireza Shahkhali was twice denied by the bar before he set up Tayebi in the 17th minute for the second goal, with Mustafa Rhyem then scoring an own goal.
Lebanon suffered more woe after Mouhammad Hammoud was forced out of the game through injury in the 18th minute, with Moslem Oladghobad then adding Iran’s fourth from distance.
There was no denying Iran’s superiority as they scored their fifth goal a minute into the restart through Bahman Jafari’s long-range effort before Oladghobad netted again seven minutes later.
Lebanon tried to stem the tide but their efforts fell flat as Iran stretched their lead in the 27th minute with Mahdi Karimi scoring from the half-way line into an unattended goalmouth before Aghapour added his second goal five minutes later from close-range.
Tayebi capped the victory in the 39th minute, beating two defenders on the turn before slotting home.
MA/TT