As the need for conservation of the national marine resources increases, the need for more and better quality data on how these resources are utilized also increases. One of the most crucial data is the data for catch per unit effort. To meet these needs, Department of Fisheries Malaysia (DOFM) has started to implement vessel logbook programs since January 2018 and these programs were initiated for the pelagic longline fisheries. Fishermen are required to report the numbers of each species caught, the numbers of animals retained or discarded alive or discarded dead (longline gear is non-selective and unwanted or prohibited species such as, billfishes, sea turtles, etc., must be returned to the water), the location of the set, the types and size of gear, and the duration of the set. Since some of the needed catch/effort information for pelagic longline fisheries remains the same for the entire trip (i.e., it would be redundant to report it for every set), a supplemental form is used to report this type of data. The length frequency data form is the important part in this log book and this data requirement will be comply to the IOTC regulation.