A last minute drop goal from Canadian captain Gareth Rees, left Cardiff ruing a number of missed chances at the Arms Park on Friday.
After a superb opening 20 minutes from the home side, Quins fought back through two drive-over tries and some superb kicking to scrape a vital away point.
After the game, Wales and Cardiff fly-half Neil Jenkins admiitted the result was not what he had hoped for.
"A draw is not great, but obviously it's better than nothing," he said.
"We'll just have to improve from here on in."
Mistakes aplenty
Rees and Jenkins each finished with 22 points, while the try-count was also shared during an error-strewn Pool E clash.
The early points all went Cardiff's way, with Jenkins slotting three penalties and Simon Hill making the most of an error from Rees to touch down wide out.
At 16-0 up the lead looked unassailable, but Quins hit back immediately with flanker Pat Sanderson and skipper Zinzan Brooke both driving over from line-outs to keep Quins in touch.
Cardiff's second came from a 5-metre scrum, with French referee Didier Mene awarding a penalty-try after the scrum collapsed for the third time.
An injury-time penalty from Jenkins seemed to have wrapped it up for Cardiff, but two penalties and two drop goals from Rees denied the Welsh side the home victory they so badly desired.
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(16 Nov 99 | Rugby Union)
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