Liverpool emerged from a tame first-half showing to create a barrage of Gerrard-inspired second-half chances, before the skipper himself blasted home a free-kick 20 minutes from time.
But just when the points seemed to be in the bag, an error from Jerzy Dudek gifted LuaLua an easy chance to level the scores, sending the Pompey fans into delirium.
Reds boss Rafa Benitez had made six changes to his starting line-up following a painful reverse in the Merseyside Derby against Everton at the weekend.
Milan Baros returned to freshen up a tired strikeforce and Xabi Alonso was
also brought back to add culture and class to the midfield.
Dudek made his first Premiership start since September, coming in for Saturday's fall guy Chris Kirkland, who was sidelined through a back injury.
The Reds looked determined to atone for their Derby disappointment and had a decent opportunity to open the scoring on eight minutes. A fine ball over the top from Alonso found Gerrard in space, but his low cross was well intercepted by Jamie Ashdown with Baros lurking.
A minute later Didi Hamann was presented with an even better chance when Antonio Nunez flicked on Gerrard's corner, but the ball arrived too quickly at the German's feet and he scuffed his shot wide.
Portsmouth almost had a surprise lead midway through the half when Steve Finnan was caught out of position, giving LuaLua a run on goal, but there were no acrobatic celebrations after he curled his effort wide at the Kop End.
Liverpool hit straight back with a decent effort from Nunez, but his first-time shot was easily saved as the Anfield crowd grew restless.
Baros was looking out of sorts, Harry Kewell hit-and-miss and Gerrard was failing to dominate.
An excellent challenge from Nunez on 37 minutes gave Kewell a golden opportunity to set the marauding Gerrard free, but the Australian international dreadfully over-hit his pass.
Five minutes before the break, a mazy run from LuaLua saw him by-pass the whole Liverpool defence, but his tame shot from a tight angle landed comfortably at Dudek's feet.
Gary O'Neil repeated the feat a minute later, but curled his shot inches wide as the visitors ended the first period much the stronger of the two sides.
Gerrard provided a much-needed inspired touch after the interval as he turned beautifully to provide space for a shot, but his effort crept over the bar.
It seemed that Benitez's undoubtedly stern half-time words had given the Reds fresh impetus and in turn the Kop raised the decibel level tenfold.
On 56 minutes, a trademark crossfield pass from Alonso found Gerrard, who nodded Nunez into the clear, but Ashdown did well to deny the Spaniard from point-blank range.
A goal was now only a matter of time, Gerrard was again the provider, this time for Hamann who somehow failed to convert a free header from six yards.
The goal did arrive 20 minutes from time, almost inevitably through the home skipper Gerrard, when he blasted a 25-yard free-kick into the top corner from Alonso's lay-off.
It was a finish that deservedly shattered Pompey's brave rearguard and after his Champions League heroics last week, Gerrard again showed a world-class touch when the Reds needed it most.
But a dreadful error from Dudek in stoppage time undid all of Gerrard's good work, as the Pole could only palm Matthew Taylor's cross out as far as LuaLua, who nodded home to seal a share of the spoils for Pompey.