Querrey, who beat compatriot Mardy Fish to win the Wimbledon warm-up event last year, made few forays to the net on the pristine center court lawn but had enough power from the baseline to dominate his opponent.
The 25-year-old Spaniard, along with the other top seeds, was given a bye in the first round and will start on Wednesday against India's Somdev Devvarman or Australia's Matthew Ebden.
From then on it was plain sailing, even if he seemed reluctant to sharpen up his volleys.
"Coming out the first day with the brand new grass was a little bit slippery, but it felt good," Querrey, who reached the last 16 at Wimbledon last year where he lost to Andy Murray, told reporters.
"I had a few jitters but I thought I served really well and moved well. I was pretty happy for my first grass court match of the season."
After the early rain cleared on a chilly day in west London, Spain's Feliciano Lopez, who beat Nadal in the quarter-finals here last year, overcame Russia's Dmitry Tursunov 7-6 6-3 to set up a clash with four-times champion Andy Roddick.
Frenchman Nicolas Mahut's first singles match on London grass since last year's freakish 11-hour 183-game epic defeat by American John Isner was a rather less memorable affair.
Mahut, runner-up to Roddick in 2007, beat British junior Oliver Golding 6-3 6-4 and will face Spanish seventh seed Fernando Verdasco next.
(Reporting by Martyn Herman; Editing by Alan Baldwin)