Superb goals from Xabi Alonso, Fernando Torres, Yossi Benayoun and David Ngog secured a 4-1 win for the Reds as Rafael Benitez' side stepped up a gear in their preparations for next week's Champions League qualifier in Belgium.
Ahead of the match, a buoyant crowd packed into the stadium to see Liverpool in action, but it was the hosts who made the more assured start to the proceedings and after a cagey opening 10 minutes it looked like the Reds could be in for a tough evening.
However, it was Rafael Benitez's side that made the first chance of any note when Fernando Torres fizzed a low drive just wide of the near post.
It set the tone for the remainder of the half and just seconds later Xabi Alonso flashed a 25-yard effort just over the crossbar after Dirk Kuyt's cross from the right had only been half-cleared by the Norwegian outfit.
It seemed only a matter of time before Liverpool would strike the opening goal of the match and after Steven Gerrard had smashed a 30-yard shot well over the bar, they duly obliged courtesy of an exquisite finish from Alonso.
A neat build-up down the right ended with Robbie Keane, who touched the ball back for the Euro 2008 winner to curl the ball beyond the despairing dive of Perkins and into the far corner of the net.
It was the Spaniard's second goal of the pre-season and followed on from his superbly executed spot-kick in the 4-0 win over Rangers four days earlier.
It was all plain-sailing for the visitors and not even the blow of losing skipper Steven Gerrard through what looked like a thigh strain on 28 minutes could stop them from dominating the remainder of the half.
Robbie Keane went close to opening his account for his new club with an 18-yard shot that arrowed just wide of target while Jamaican defender Adrian Reid - who was making his Valerenga debut - was left to breath a huge sigh of relief when he saw his awkward defensive header crash back off his own post.
The Norwegians had been almost non-existent as an attacking force in the opening 45 minutes and so it came as a huge surprise to those packed inside the Ullevaal Stadion when they drew level within two minutes of the restart.
A flowing one-touch move down the right opened up the Liverpool defence allowing Bojan Zajic to coolly dispatch the ball beyond substitute keeper Pepe Reina and spark huge celebrations amongst his Valerenga teammates.
The home support began to dream of a shock Valerenga victory but the goal only served to shake the Reds into action and within 60 seconds normal service had been resumed courtesy of another virtuoso strike from Fernando Torres.
The Spanish hot-shot latched onto Dirk Kuyt's intelligent header before surging beyond Reid and nonchalantly slotting the ball past another substitute keeper, Bolthof, to put Liverpool 2-1 ahead.
From that moment on the pattern of play began to resemble that of the first period and Keane was once again cursing his luck less than a minute later when he dragged a low effort just wide after he was played through on the left side of the penalty area.
It was a frustrating night for the Irishman who is still to open his account for his new club although he did at times show glimpses of the quality he will offer Rafael Benitez's side.
The Reds boss once again opted to mix it up with a series of substitutions midway through the second-half but not before Yossi Benayoun made it 3-1 with a magnificent individual goal on the hour mark.
The Israel international slalomed his way past three defenders before clipping a rising shot over the keeper and into the far corner of the Valerenga net.
By now the Norwegians had run out of steam and there was even time for a fourth when substitute David Ngog raced into the area to fire home his second goal in as many games.
It meant the same four players who were target in the 4-0 mauling of Rangers at the weekend had found the net again and reiterated the strength in depth Benitez now has at his disposal.
Teams
Valerenga: Perkins, Jepsen, Muri, Reid, Storbaek, Berre, Heastad, Strand (c), Zajic, Holm, Shelton. Subs - Bolthof, Dos Santos, Fellah, Haidar, Jalland, Nouri, Singh, , ,Liverpool: Cavalieri, Dossena, Agger, Carragher, Arbeloa, Benayoun, Alonso, Gerrard (c), Kuyt, Keane, Torres. Subs - Darby, El Zhar, Hyypia, Insua, Nemeth, Ngog, Pacheco, Plessis, Reina, Spearing
