The win took Iran to 15 points in the table. Team Melli's hopes of advancing to the final round for the FIFA World Cup Qatar 2022 Qualifiers are firmly in its own hands.
Cambodia, meanwhile, ended its campaign with just one point to its name from eight matches.
Cambodia suffered a setback in the 15th minute when Iran was awarded a penalty after defender Sor Rotana’s foul on Alireza Jahanbaksh, with the Iran skipper converting the spot-kick.
Iran continued to press and was rewarded again with Shojae Khalizadeh rising highest to head home a corner kick in the 22nd minute, before Mehdi Taremi got into the goalscoring action with a half-volley to make it 3-0 five minutes later.
Iran’s fourth goal came through Rotana deflecting Milad Mohammadi’s cross past custodian Keo Soksela in the 32nd minute.
Iran maintained a high tempo in the second half with Milad Mohammadi etching his name on the scoresheet in the 57th minute, before Morteza Pouraliganji headed home a corner six minutes later.
Cambodia's desperate defending led to another Iran penalty in the 77th minute, with Karim Ansarifard slotting home to make it 7-0.
There was no stopping Iran’s quest for goals, with Kaveh Rezaei becoming the seventh Team Melli player to find the back of the net after heading in Sadegh Moharammi’s cross in the 80th minute, before Mehdi Ghayedi displayed his dribbling talent in the box to beat Soksela from close range.
Rezaei bagged his second of the night in the 87th minute as Iran completed an emphatic win and set its sights on Iraq.