Seven of their goals came in a devastating second-half display as Liechtenstein crumbled after frustrating their hosts early on.
Diego Costa, David Silva and Alvaro Morata all scored twice while Sergi Roberto and Vitolo also got on the scoresheet in the Group G opener.
It made for a perfect first competitive game for new coach Julen Lopetegui, who would actually have been concerned at his side’s lack of cutting edge at half-time.
Spain started well, with Koke curling an inviting free-kick into the area and Costa rising superbly to head home from six yards.
But, surprisingly, that proved one of few fluid moves the hosts produced before the break.
It was not until the 40th minute Lopetegui’s men threatened a second as Koke’s scuffed shot was cleared off the line by Franz Burgemeier. Vitolo should have headed in the rebound but failed to make firm contact and Sergio Busquets then shot against Vitolo in the ensuing goalmouth scramble.
Liechtenstein escaped again when Costa headed another chance wide but it became only a matter of time as Spain upped the tempo after half-time.
Silva should have scored after going through on goal but he allowed keeper Peter Jehle too much time to save before Koke hit the post from a free-kick.
The second finally came after 54 minutes as Nolito turned and slipped in Roberto with a clever pass and the latter’s first-time toe-poke beat Jehle.
Liechtenstein then began to fall apart as three more goals followed in little more than 10 minutes.
Vitolo got behind the defence and teed up Silva, who smashed in a shot off the bar from three yards. The visiting defence were then all at sea as Nolito clipped a ball into the box and a quick exchange of passes between Costa and Silva set up a simple finish for Vitolo.
Costa nodded in the fifth after 66 minutes. The Chelsea striker was initially denied by the legs of Jehle after a neat turn but the keeper could not keep out the second attempt as Costa headed the rebound into the roof of the net.
Costa may then have backed himself to score a hat-trick but that proved his last meaningful involvement as he was removed by Lopetegui just two minutes later.