Azmoun, who has recently joined AS Roma, is recovering from an injury he suffered in Bayer Leverkusen a few weeks ago.
Iran coach Amir Ghalenoei has called up 24 players for the warm-ups.
Iran is scheduled to meet Bulgaria on September 7 at the Hristo Botev Stadium in Plovdiv and will host Angola in Tehran on September 12.
The friendly matches serve as a stepping stone towards Iran's 2023 AFC Asian Cup aspirations, where the team is drawn in Group C along with the UAE, Hong Kong and Palestine.
Squad:
Goalkeepers:
Alireza Beiranvand (Persepolis), Payam Niazmand (Sepahan), Mohammad Reza Akhbari (Gol Gohar)
Defenders:
Milad Mohammadi (AEK Athens), Ehsan Haj Safi (AEK Athens), Ramin Rezaeian (Sepahan), Mohammad Daneshgar (Sepahan), Sadegh Moharrami (Dinamo Zagreb), Morteza Pouraliganji (Persepolis), Rouzbeh Cheshmi (Esteghlal), Hossein Moradmand (Esteghlal)
Midfielders:
Alireza Jahanbakhsh (Feyenoord), Milad Sarlak (Persepolis), Saeid Ezatolahi (Vejle Boldklub), Vahid Amiri (Persepolis), Ali Alizadeh (Gol Gohar), Saman Ghoddos (Brentford), Ahmad Nourollahi (Al Wahda), Ali Karimi (Kayserispor), Mohammad Mohebbi (Rostov), Mehdi Torabi (Persepolis)
Forwards:
Mehdi Taremi (Porto), Shahriyar Moghanlou (Sepahan), Reza Asadi (Sepahan)