Blue swimming Crab (Portunus pelagicus) is found in large numbers in the Betahwalang waters, and they are mainly caught using traps. Betahwalang fishing communities have realised the importance of preserving this commodity of blue swimming crab (Portunus pelagicus) by enlarging crab conservation zone in the territorial waters of betahwalang. However, many fishermen catch blue swimming crab and sell them. The capture of small crab egg-laying females cannot be avoided because the mouth traps folding reaches 29 cm. Modifications are made to reduce the capture of spawn female crabs by changing the shape of the mouth traps from a rectangular into a circular shape with a certain diameter. This research uses an experimental fishing method. Data is analysed using SPSS 16.0. The results indicate catching Blue Swimming Crabs using modified funnel and different baits (pony fish essence) is effective in landing a big catch. The catch was relatively bigger. This research also shows a positive link between modified trap and use of different baits to catch Blue Swimming Crabs.