González was born in Durban, South Africa. His father Raúl was a professional footballer for Durban Bush Bucks, and named him after his friends and fellow footballers Mark Tovey and Dennis Wicks. He left South Africa aged 10 in 1994 and moved back to Chile with his mother.

González had agreed a move to Liverpool on loan for the 2005–06 season (with a view to a permanent £1.5 million move) from Albacete. However, he was denied a work permit by the Department of Education and Employment in August 2005. The Liverpool management showed great faith in González, pursuing his services despite work permit troubles and a cruciate knee ligament injury. After a quicker-than-expected return to fitness, Liverpool were persuaded to make the move permanent in October 2005, but the player was immediately loaned back to Albacete to continue his recuperation after an appeal against the earlier work permit decision was rejected (a new work permit application can only be put forward one year after the original application). Arrangements were then made for the player to spend a loan spell at Real Sociedad until summer 2006.

González was presented on loan at Real Sociedad on 30 January 2006, until 30 June, alongside Jhon Viáfara, whom the club had loaned from Portsmouth. González said that at Sociedad he would aim to improve his tactical play.

On 5 July 2006, González was granted a work permit, and was allowed to start his Liverpool career, wearing the number 11 shirt. His manager, Rafael Benítez, said, “This is very good news for us and I am absolutely delighted to welcome Mark González to Liverpool as he is a player the supporters will like to see.” González made his first appearance as a half-time substitute for fellow debutant Fábio Aurélio in a pre-season friendly away against Crewe Alexandra on 22 July.

González made his competitive debut on 9 August 2006 against Israeli side Maccabi Haifa, coming off the bench in the 85th minute for Steven Gerrard and scoring an 88th-minute winner in Liverpool’s Champions League 3rd Round Qualifier to seal a 2–1 win. He scored his first Premier League goal in Liverpool’s 3–0 win over Tottenham Hotspur on his first league start for the club on 23 September. He scored just once more for Liverpool, in a 4–0 win over Fulham on 10 December.

González was injured inside the first ten minutes of the quarter-finals of the League Cup against Arsenal on 9 January 2007 as a result of a challenge on Theo Walcott. He was brought off on a stretcher for Luis García, who was also taken off injured later in the match as Liverpool lost 3–6. He played his last game for Liverpool on 5 May 2007 against Fulham in a 1–0 defeat.

On 24 May 2007, Rafael Benítez confirmed that Liverpool had almost reached an agreement with Real Betis over the Chilean winger. On 12 June, González confirmed that he had signed a contract for £5 million with Real Betis, who presented him to the press and fans on 17 July 2007. He went on to score on his home debut with a penalty goal in the 1–0 victory over Champions League holders Milan in the Centenary Match in front of 55,000 fans. González scored in a famous 2–1 victory over high-flying Real Madrid to steer Betis out of the relegation zone in La Liga. He ultimately scored ten goals in 44 first-team appearances for the club. Betis received an offer of €11 million from an unnamed club in July 2008.

González began dating Chilean television personality and model Maura Rivera in 2008, and they married in 2010. They have one son, Mark González, Jr. In 2015, they welcome their daughter Luicana González.

In June 2009, following the relegation of Real Betis, Greek double holders Olympiacos made an offer of €3 million to secure him a starting eleven position in their squad for the forthcoming Champions League, but CSKA Moscow offered €6.5 million and on 11 August 2009, he signed a five-year deal with the Russian club. He debuted for the club on 16 August 2009 in a league match away to Lokomotiv Moscow.

On 6 December 2010, it was reported that he had been accused of rape in Moscow. However, later the same day the investigators announced that the accused was an unrelated Portuguese citizen named Mario Gonzalez, who is also allegedly a professional footballer.

On 21 June 2010, González scored the only goal of the game for Chile against Switzerland during the group stage of the 2010 FIFA World Cup in his birthplace South Africa, heading in a cross from Esteban Paredes.

On 21 January 2014, CSKA announced that González had left them to join Universidad Católica in Chile on loan. In December 2014, González had his CSKA contract terminated by mutual consent.

Originally a loan, González joined his first professional club Universidad Católica in Chile in January 2015 after spending ten years abroad. After the mutual termination of his contract at CSKA, he joined Católica on a permanent move as a free agent. He helped the team with nine goals in the campaign, which Católica won. It was also González’s first Primera División win after previously finishing second in the 2002 Clausura.

On 4 January 2016, González rescinded his contract at Universidad Católica and joined Brazilian club Sport Recife for the next two years. He made his debut on the 31st, playing the full 90 minutes as they lost 1–0 at Salgueiro Atlético Clube in the 2016 Campeonato Pernambucano first match of the year. He played only one more game before being sidelined for a month by a thigh injury, and totalled seven appearances as they finished runners-up to Santa Cruz.

On 30 December 2016, it was announced that González has signed for Chilean club Colo Colo.