Mostafa Kiani was on target just 33 seconds into the match. Mohammad Moradi made it 2-0 in 4th minute.
Azerbaijan’s Abdul Aliyev pulled a goal back in 7th minute.
Kiani scored once again in 16th minute and Asif Zeynalov reduced the deficit in 32nd minute.
Spain also defeated Ukraine 6-2 in Day 1.
Iran has been scheduled to meet Ukraine on Sunday while Spain face Azerbaijan.
The competition is being held in Bushehr, south Iran from January 27 to 29.
The Iranian team won the title in the first edition, defeating the national Italian beach soccer team – nicknamed Gli Azzurri (The Blues) – 4-3 in the final showdown on February 16, 2017.