Hamed Haddadi, formerly of the Phoenix Suns and Memphis Grizzlies, had 16 points and 4 rebounds for Iran.
Greek Giannis Antetokounmpo finished with 16 points on an efficient 7-of-8 shooting from the field, including 2-of-3 from three-point range.
Iran has been scheduled to face Mexico on Tuesday.
Six teams are split into two groups for a FIBA Olympic qualifying tournament in Turin, Italy. Group A has Greece, Mexico and Iran, Group B has Tunisia, Croatia and Italy.
Nine teams have already punched their ticket to Rio de Janeiro.
The top two of each pool play off in the crossover round.
The first-place team in Group A will take on the second-place team from Group B in one semi-final, and the side that comes top of Group B will go up against the second-top team in Group A in the other semi-final.
The winners will then meet in a do-or-die showdown for a spot in the Olympics.