The Regional Workshop on Monitoring Control and Surveillance (MCS) for Combating IUU Fishing in Southeast Asia was organized from 23 to 24 August 2022 by SEAFDEC Training Department (SEAFDEC/TD) at Pattaya, Chonburi Province, Thailand. The aims are to share and update information on MCS implementation activities to combat IUU fishing, enhance and promote fisheries management tools for combating IUU fishing, and identification of the need for capacity building on MCS for combating IUU fishing. There were 37 participants from the ASEAN Member States and international organizations attending this workshop. The implementation of MCS activities was presented and shared by AMSs and international organizations such as FAO, AN-IUU, RPOA-IUU, International MCS Network (IMCS), Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR), Indian Ocean Tuna Commission (IOTC), Australian Fisheries Management Authority (AFMA), Southern Indian Ocean Fisheries Agreement (SIOFA). In the end, the workshop came up with updated information on MCS implementation activities to combat IUU fishing among AMSs, understanding fisheries management tools for combating IUU fishing, and capacity building need on relevant MCS for combating IUU fishing. The workshop is an activity under the project “Strengthening Regional Cooperation and Enhancing National Capacity to Eliminate IUU Fishing in Southeast Asia”.