The new deal means Del Bosque will continue at the helm of the reigning world and European champions until 2016.
Del Bosque said at a press conference on Friday: "I can confirm that I have signed with the Spanish national team until 2016."
Del Bosque, 62, took over as Spain coach five yeas ago after Luis Aragones stepped down shortly after guiding the Iberian nation to victory at Euro 2008.
That was Spain's first international success since winning the 1964 European Championships on home soil, and under Del Bosque they have gone from strength to strength.
In 2010 they lifted the World Cup for the first time in their history after beating Holland 1-0 after extra-time in the final in Johannesburg.
Then two years later Spain retained their European title in Poland and Ukraine, lifting the trophy with a 4-0 drubbing of Italy in the final after going through the tournament unbeaten.
Spain also had the chance to add the Confederations Cup crown to their list of accolades this summer after reaching the final, but they were beaten 3-0 by hosts Brazil.
That was one of only six defeats Spain have suffered in 82 matches under Del Bosque, with the team claiming victory on 67 occasions.
Spain will be expected to improve that record further this weekend when they take on Equatorial Guinea in a friendly in Malabo, where Del Bosque was speaking from on Friday.
Following that match, Spain travel to Johannesburg to play South Africa next Tuesday as they look to finish 2013 on a high note.
Before taking up the Spain post the Salamanca-born Del Bosque had been out of coaching since leaving Turkish side Besiktas in 2005 after a disappointing spell.
However, prior to that he enjoyed a hugely successful career at Spanish giants Real Madrid, both as a player and a coach.
During his playing days Del Bosque won five Primera Division titles and four Copa del Reys with Madrid, while he also won 18 caps with Spain.
Once he hung up his boots in 1984 Del Bosque turned his hand to coaching, where, after making his way up through the ranks from the Madrid youth team to the senior side, he earned himself legendary status at the Bernabeu by winning seven trophies in four years at the turn of the millennium.
Among those triumphs were two Champions League titles in 2000 and 2002 - the last times the Spanish giants have lifted the European Cup - and two Primera Division crowns.
That sustained spell of success failed to save Del Bosque in 2003 though when, just 24 hours after leading Madrid to their 29th league championship, he found out that his contract was not being renewed.
After that controversial end to his time at Madrid, Del Bosque took the reins at Besiktas in 2005 but lasted less than a year before leaving the club.