Born in Levski, Pleven Province, Milanov began playing football at the local club, before joined the Litex Lovech Academy, together with his twin brother Iliya, in 2005.
He was part of a group of young players at the club who guided the club to win the Bulgarian U-17 Championship in June 2009, with Milanov scoring in the final against Levski Sofia.

On 1 August 2009, Milanov made his first team debut, at 17 years 152 days, coming off the bench in the 2009 Bulgarian Supercup against Levski Sofia, which ended in a 1–0 defeat at Vasil Levski National Stadium.
A week later, he made his league debut against Lokomotiv Mezdra, scoring the opening goal in a 5–0 victory.
On 3 December, he scored his first ever Bulgarian Cup goal, in a 4–0 win over Pirin Gotse Delchev which sent them through to the 1/8 finals.
Milanov play regularly in his first season, making 31 appearances in all competitions and collected his first A PFG title winner's medal at the end of the 2009–10 season.

On 14 August 2010, in a 2–1 home victory over Pirin Blagoevgrad, Milanov netted his first goal of 2010–11 season.
He ended his second season with 5 goals in 36 appearances in all competitions.
Milanov helped Litex retain the A PFG title by a 3-point margin after being pushed by Levski Sofia for much of the season.

In 2011–12 season, Milanov scored 6 goals in 25 league matches.
On 24 May 2012, he was credited with the ABF A PFG Young Player of the Season award, by the professional footballers association of Bulgaria.

On 19 August 2012, Milanov scored his first goal of 2012–13 season in a 1–1 away draw against Lokomotiv Plovdiv.
On 27 October, he scored his first ever hat-trick in the A PFG, against Montana, in a 3–1 victory at Ogosta Stadium; he scored from a penalty kick and a two free-kicks.
On 27 December 2012, he became the youngest ever recipient of the Bulgarian Footballer of the Year award.
On 30 March 2013, as a result of injuries to regular captains Nebojša Jelenković and Nikolay Bodurov, Milanov captained Litex for the first time against Botev Vratsa in a 5–1 home win.
On 14 April, he played his 100th match for Litex in the league in a 2–1 away loss against Slavia Sofia.
Born in Levski, Pleven Province, Milanov began playing football at the local club, before joined the Litex Lovech Academy, together with his twin brother Iliya, in 2005. He was part of a group of young players at the club who guided the club to win the Bulgarian U-17 Championship in June 2009, with Milanov scoring in the final against Levski Sofia. 
On 1 August 2009, Milanov made his first team debut, at 17 years 152 days, coming off the bench in the 2009 Bulgarian Supercup against Levski Sofia, which ended in a 1–0 defeat at Vasil Levski National Stadium. A week later, he made his league debut against Lokomotiv Mezdra, scoring the opening goal in a 5–0 victory. On 3 December, he scored his first ever Bulgarian Cup goal, in a 4–0 win over Pirin Gotse Delchev which sent them through to the 1/8 finals. Milanov play regularly in his first season, making 31 appearances in all competitions and collected his first A PFG title winner's medal at the end of the 2009–10 season.
On 14 August 2010, in a 2–1 home victory over Pirin Blagoevgrad, Milanov netted his first goal of 2010–11 season. He ended his second season with 5 goals in 36 appearances in all competitions. Milanov helped Litex retain the A PFG title by a 3-point margin after being pushed by Levski Sofia for much of the season.
In 2011–12 season, Milanov scored 6 goals in 25 league matches. On 24 May 2012, he was credited with the ABF A PFG Young Player of the Season award, by the professional footballers association of Bulgaria.
On 19 August 2012, Milanov scored his first goal of 2012–13 season in a 1–1 away draw against Lokomotiv Plovdiv. On 27 October, he scored his first ever hat-trick in the A PFG, against Montana, in a 3–1 victory at Ogosta Stadium; he scored from a penalty kick and a two free-kicks. On 27 December 2012, he became the youngest ever recipient of the Bulgarian Footballer of the Year award. On 30 March 2013, as a result of injuries to regular captains Nebojša Jelenković and Nikolay Bodurov, Milanov captained Litex for the first time against Botev Vratsa in a 5–1 home win. On 14 April, he played his 100th match for Litex in the league in a 2–1 away loss against Slavia Sofia.
Georgi Milanov (footballer)