One of the comparison methods for evaluating fishing gears efficiencies is based on Catch per Unit Effort (CPUE). In this study, we used three different types of traps for catching oriental river prawn (Macrobrachium nipponense). Capture efficiencies and catch rates of cylindrical pot, opera house trap, and Hokkaido pot were compared with each other during the investigation in Anzali Lagoon. The results indicated that there is a significant difference (P˂0/05) among the amounts of CPUE of cylindrical pot (0.24±0.12 gr), opera house trap (4.17±0.84 gr) and Hokkaido pot (1.58±0.41 gr). There was a significant difference between the results of length frequencies of captured prawns that was trapped by cylindrical pot and opera house trap (P<0.05). Hokkaido, cylindrical and opera house traps were not significantly different from each other for length frequencies. The results indicated that opera house trap was an appropriate fishing gear for catching oriental river prawn because it had higher catch rates and caught prawns with higher length frequencies.