Wood skippered the Red Rose to a 2-0 series win in Argentina this summer during Robshaw’s absence and coach Stuart Lancaster is so far unwilling to commit to his choice of leader for the fixtures with Australia, Argentina and New Zealand at Twickenham.
But O’Shea believes there is only one man for the job.
“I have no doubt that when it is picked Chris will be England captain,” said O’Shea.
“Chris is in great shape and great form. I can’t think of anyone else.”
Quins have made an indifferent start to their Aviva Premiership campaign, with three defeats from their opening five matches, and are seventh in the table.
But with back-to-back Heineken Cup pool games to come before England meet for a training camp on 21 October, Lancaster believes there is ample time for his captaincy candidates to prove their credentials.
“We have two big European weekends and I’ve consistently said you must select on form and fitness first,” said Lancaster.
“Equally there’s no need to announce a captain early when it might influence what you’re thinking selection wise.
“If you name the captain early then you’re pretty much ruling out everybody else playing in that position and I want to keep competition for places high.”