Iran’s Amin Esmaeilnezhad scored 16 points and Moritz Reichert earned 11 points for Germany in Rotterdam, the Netherlands.
Iran will meet Italy on Wednesday.
Behrouz Ataei’s men will face the US and the Netherlands on Friday and Saturday, respectively.
The Preliminary Phase campaign started on June 6 and includes matches in Nagoya (Japan), Rotterdam (the Netherlands) and Anaheim (USA).
If Iran qualifies for the VNL Finals as one of top eight teams, it will travel to Gdansk, Poland for the event from July 19 through 23.