After a goalless first half, Egypt captain Ahmed Fathi scored an own goal before Denis Cheryshev struck and Artem Dzyuba added a third.
The European champions took the lead in the fourth minute when Cristiano Ronaldo charged into the box to bury his header and become Europe's top global scorer with 85 goals.
The goal came on the heels of Ronaldo saving a point for Portugal against Iberian rivals Spain, as he delivered a flawless free-kick equaliser to complete his hat-trick in a 3-3 draw in their World Cup opener.
However, it also seems that some referees struggle to control themselves when around global icons such as Ronaldo and Lionel Messi, as well as cope with the pressures on going during a game.
Cristiano Ronaldo has disclosed why he is growing a beard during this summer's World Cup finals.
The Portugal star did, however, miss one spot kick at the venue for today's game, Luzhniki, in a shootout in the Champions League Final in 2008 - although he scored in normal time and his Manchester United team went on to win the title regardless. "We are the Portuguese national team and we have to beat Morocco".
At an age when most players are winding down, Ronaldo is flourishing, defying his advancing years by becoming even more prolific as he gets older.
Yet aside from the goal, it was not a vintage display by Ronaldo or Portugal, who were caused problems by a spirited Morocco team.
They qualified for the finals without conceding a goal in six matches yet somehow opted against marking the most unsafe attacker at the tournament in the six yard box when Joao Moutinho swung in a cross from a short corner and Ronaldo duly buried the header.