Amir Ghafour top scored Iran with 13 points, and Seyed Mohammad Mousavi and Mojtaba Mirzanjapour added 12 and 10 points, respectively.
Kervin Pinerua, who was the lone bright spot in the Venezuelan offence, finished with 10 markers.
Iran started the campaign with a 3-1 loss to Argentina but defeated Tunisia 3-1 in its second match.
The Iranian team will play Poland on Saturday.
The tournament is a qualification process for the 2016 Summer Olympics in Rio de Janeiro, Brazil.
The top two teams will qualify for the Olympics and join Brazil as it has already secured a berth as the host country.
The 2015 FIVB Volleyball Men’s World Cup began on September 8 in Japan and will finish on September 23.