Fernando Torres scored four times and David Villa claimed a hat-trick for the world and European champions at Rio's hallowed Maracana, with David Silva adding a brace and Juan Mata also finding the net.
No team had previously won by 10 goals at an international FIFA event, with Hungary (9-0 against South Korea at the 1954 World Cup, 10-1 against El Salvador at the 1982 World Cup) and Yugoslavia (9-0 against Zaire at the 1974 World Cup) the co-holders of the previous record.
Tahiti, who sit 138th in the FIFA ranking, equalled their heaviest defeat — a 10-0 demolition by New Zealand in 2004 — but Spain fell short of matching their 13-0 annihilation of Bulgaria in a 1933 friendly.
"It's a very nice result. The difference between the two teams was too great," said Spain coach Vicente del Bosque.
"But we played our game and they have a way of playing that is correct. They're a very noble team."
Spain will be assured of a place in the semi-finals if Nigeria avoid defeat against Uruguay in Salvador later in Group B.
The same outcome would also end Tahiti's mathematical chance of reaching the last four.
Tahiti coach Eddy Etaeta said the reception his part-time players had received from the Brazilian crowd represented a "great victory".
"We've won the hearts of the fans," he said. "'Obrigado' (thank you, in Portuguese) to everyone."
Del Bosque made no less than 10 changes to his starting line-up, with only centre-back Sergio Ramos keeping his place in the team from the 2-1 win over Uruguay.
Tahiti's players presented their opponents with necklaces and pendants prior to kick-off, but the pleasantries did not last long, as Torres beat goalkeeper Mickael Roche at his near post to give Spain a fifth-minute lead.
Roche was drafted into the Tahiti team in place of Xavier Samin, who shipped six goals against Nigeria, and the newcomer momentarily looked set to play the hero, saving at Torres' feet and repelling Santi Cazorla's half-volley.
His resistance did not last long, however, as Spain scored three goals in the 14 minutes before half-time to banish any hopes of a shock result.
Silva found the bottom-left corner from Villa's pass in the 31st minute, with Torres dinking the ball over the advancing Roche and rolling home before Villa got on the score-sheet from Silva's low cross.
Tahiti surprisingly enjoyed 37 percent of possession in the first half, but Del Bosque added another attacking player at half-time in Jesus Navas and Villa soon made it 5-0 from a low Nacho Monreal cross.
Torres completed his hat-trick in the 57th minute, side-footing home from Navas' cut-back, before Villa matched his strike partner by tapping in after Roche allowed a long pass to squirm through his grasp.
Mata drove in Spain's eighth shortly afterwards, and although Torres then put a penalty against the crossbar, he quickly atoned by rounding Roche to roll in his fourth goal.
Navas teed up his new Manchester City team-mate Silva for the record-breaking 10th goal in the 89th minute, by which time Spain's celebrations had become rather sheepish.