The optimal number of vessels and navigation equipment required for carrying cargo in the Karun River has been investigated in this research. At the beginning of the research, the limited studies that have been done for economic transportation in Karun have been analyzed. Then, three pessimistic, probable and optimistic values ​​have been assumed for the annual load carried by the river. Then, various proposed vessels for transportation from Arvand and Bahman Shir routes and from different sources (Mahshahr or Khorramshahr to Ahvaz and vice versa) and all types of navigation equipment have been examined. The number and types of vessels needed for river transport of different tonnages were analyzed economically. In the studies, attention has been paid to the amount of sediment required for the dimensions of the waterway channel, possible navigation speeds, factors reducing the navigation speed such as monsoon winds, dust and drought, and other variables. Finally, the specifications of the required navigation equipment have been determined and the number of floats required for the river traffic from Bandar Imam, Bahman Shir, Ahvaz to transport 0.5, 1, 2, 4 and 8 million tons of goods (iron ore) respectively equal to 5, 10, 20, 34 and 67 devices are estimated. The practical and optimal result of this research is the use of 7 vessel units with the proposed dimensions intended to carry 0.7 million tons of goods in the target year of 2046.