The controversial forward only arrived from Roma last week, but showed he can be a major star in English football, netting two goals in his first start for the club.
Mido has signed on an 18-month loan deal, but on the evidence of this display could be signed up a lot earlier on a permanent basis.
Tottenham boss Martin Jol handed an immediate debut to £4.5million signing Andy Reid and also gave a first start to the Egyptian striker.
Noureddine Naybet made a timely return at the heart of the Spurs defence as Anthony Gardner was ruled out with a broken nose.
And it was the home side who started the brightest and could have opened the scoring after just two minutes.
Simon Davies, back in the side after a lengthy spell on the sidelines laid the ball back to Mido on the edge of the penalty box. The young forward fired a blistering shot which flew just over the crossbar.
Mido continued to cause all kinds of problems for the Portsmouth in his first ever Premiership encounter.
In the fifth minute his pin-point cross picked out Stephen Kelly inside the box, whose close-range header produced a comfortable save from Kostas Chalkias in the Portsmouth goal.
And just 60 seconds later the home side came close to breaking the deadlock once again when Reid's corner fell to Ledley King, but the Spurs skipper dragged his shot wide of the goal.
Mido was involved in the heart of the action again on 13 minutes when his cross-shot was turned inches past his own post by Portsmouth defender Arjan de Zeeuw.
Portsmouth had to wait until the 26th minute before creating their first opportunity of the game. Patrik Berger raced unchallenged towards the Tottenham box, but fired his shot well wide of the goal.
And completely against the run of play, Portsmouth managed to take a shock lead on 28 minutes.
Berger's corner picked out Diomansy Kamara who made no mistake powering a header past the stranded Paul Robinson in the home goal.
The home side had strong claims for a penalty turned down on 31 minutes. Mido's lay-off released Jermain Defoe into the box.
Defoe was through on goal and looked to be brought down by Dejan Stefanovic, but referee Steve Dunn waved for play to continue much to the disgust of the Tottenham dug-out.
But the home side and Mido in particular finally got their just rewards when they snatched an equaliser on 33 minutes.
Davies cross into the box found Mido completely unmarked and he made no mistake this time planting his header into the back of the net.
Portsmouth had a goal disallowed on 42 minutes when Kamara was adjudged to have handled the ball when he took the ball around Robinson and slid the ball into an empty net.
Mido continued to look lively in the second half and made a clever turn on the edge of the box on 54 minutes and fired a shot which produced a fine save from Chalkias.
And it came as no surprise when Mido added his second of the game on 57 minutes. Defoe weaved his way into the box before drilling the ball across goal.
Mido was in the right place to slide the ball home and become an instant hero with the Tottenham faithful.
Reid almost marked his debut with a goal on 81 minutes when his shot from the edge of the box came back off the post.
But substitute Robbie Keane ensured all three points for the home side on 83 minutes.
Man of the Match: Mido - The on-loan forward made a perfect start to life at White Hart Lane with two goals and he had chances to complete a hat-trick.