Quins have lost their last three matches ahead of Sunday's tie at The Stoop, but Robshaw has insisted that they remain confident of success against the Irish giants.
The skipper also believes that his side have improved considerably since the last time they faced Munster in this competition four years ago.
He told Sky Sports News: "It's not a loss of form, we played extremely well against Gloucester and were unlucky.
"You don't get these opportunities in Europe too often and you have to make them count.
"Our fans have been terrific and we want to reward them this weekend. We know the intensity and passion Munster will bring and hopefully we can use that to our advantage."
The 26-year-old was rested last weekend as Quins suffered a narrow 17-15 defeat to Gloucester in the Aviva Premiership.