The Lions ran in eight tries – with seven of them coming from Welshmen. Captain Paul O'Connell was the only non-Welshman to get over as he scored the opening try of the Tour while scrum-half Mike Phillips and winger Alex Cuthbert helped themselves to two tries each.
Jonathan Davies, Dan Lydiate and replacement Alun Wyn-Jones also went over on a day when Warren Gatland decided to start with nine Welsh players and 11 Lions debutants.
England's Owen Farrell had an up and down performance at fly-half before being replaced by Ireland's Jonny Sexton who himself missed three, admittedly tough, conversion attempts.
Kahn Fotuali'I off a lovely set-up from former All Black Joe Rokocoko scored the only try for an enthusiastic, but ultimately outmatched Barbarians side who should have had Schalk Brits sent-off for a clear punch on Farrell after just eight minutes only for referee Steve Walsh to let him off with a yellow card "because of the game."
Over 10,000 empty seats in the 40,000-capacity Hong Kong Stadium struggled to give this essentially money-making fixture much credibility but the Lions Tour of Australia starts proper with a clash in Perth against Western Force on Wednesday with a further four matches being played before the first Test in Brisbane on June 22.
The Lions had to wait until the 28th minute to get their opening score but O'Connell finally went over from close-range after Phillips had been held up just short. Before that moment the score was still 3-3 but the Lions never looked back.
Phillips rolled and finished off a tackle to get the Lions' second try before the break and the tourists went in at half-time leading 23-3.
Phillips scored his second just after the break to make it 30-3 and help stake his case for a Test place at scrum-half ahead of Ben Youngs and Conor Murray but the Baa-Baas reduced the deficit in the 56th minute when Fotuali'I started and finished a one-two with Rokocoko that was a joy to watch, as Rokocoko showed he has still got it by burning past Toby Faletau to set up the score.
In sticky, humid conditions though, the Lions' superior fitness was always going to be key as the Barbarians were unable to handle the Lions scrum while also struggling to defend the line-out.
Davies scored a scrappy fourth try for the Lions before man-of-the-match Phillips set up Alex Cuthbert for a try down the left with his final action before being replaced by Murray.
Cuthbert scored a similar try down the left for his second – this time set-up by Irish scrum-half Murray – and then Lydiate made it 52-8 from close range in the 76th minute.
The final try came right on the 80 minutes as Wyn-Jones went over after a great pass by Sexton.
It was a solid outing for the Lions – there were some handling errors they will look to iron out although they can be partially explained by the conditions – but Gatland won't learn much about his team until they encounter tougher tests Down Under - starting in Perth on Wednesday.