Vidima-Rakovski In his youth years in
Botevgrad, Iliev started to play football at
Balkan. He joined
Vidima-Rakovski when he was fourteen years old and signed his first professional contract in 2009. At the beginning of the 2009–10 season, Iliev was added to Vidima's senior squad by manager
Dimitar Todorov. He made his
B Group debut in the starting line-up on 8 August 2009 in a 1–1 draw against
Kom-Minyor. During the season he became first choice goalkeeper and earned 23 appearances, helping his team to win promotion to the
A Group. Iliev was also the first choice keeper for the team from
Sevlievo in the first half of the 2010–11 season and earned praise for his performances.
Levski Sofia On 17 December 2010, Iliev was sold to
Levski Sofia. He made his debut for Levski against
Lokomotiv Sofia on 6 March 2011, with Iliev succeeding in keeping a
clean sheet. On 6 April 2012, Iliev was appointed as Levski's captain, but became vice-captain for the 2012–13 season, as new coach
Ilian Iliev decided to give the captain's armband to
Stanislav Angelov. On 14 September 2012, Iliev signed a new contract keeping him at the club until 2016.
Botoșani On 5 June 2015, Iliev moved abroad for the first time, agreeing to a three-year deal with Romanian
Liga I club
FC Botoșani.
Astra Giurgiu Following his good display at Botoșani, Iliev was signed by defending champions
Astra Giurgiu on 1 February 2017. He kept a clean sheet in his competitive debut against
Politehnica Iași, with Astra conceding two goals before his substitution. On 3 April, Iliev saved two penalties in six minutes, but in an eventual 1–2 home loss to
Viitorul Constanța. After the departure of
Silviu Lung Jr. to
Kayserispor in the summer of 2017, Iliev became the starting goalkeeper for Astra.
Ludogorets Razgrad On 7 January 2019,
Ludogorets Razgrad confirmed that Iliev had signed a preliminary contract under the
Bosman ruling and is set to join the team as a free agent in June 2019 if the negotiations between Astra and Ludogorets in January didn't end with a transfer agreement, but on 12 January the teams reached an agreement and Iliev joined the team for an undisclosed fee.
Dinamo București After being released from Ludogorets, Iliev returned to Romania, signing a contract with local giants
Dinamo București.
Cherno More Varna In June 2024, he made a return to his country, joining
Cherno More. ==International career==