SEAFDEC Training Department (SEAFDEC/TD) organized the “Regional Training Course on The Principle of Hydroacoustic Survey by Quantitative Echosounder (EK80) and Data Analysis” from 7 to 15 October 2024 at SEAFDEC/TD, Samut Prakan, Thailand which the main aimed to capability building of researchers in effectively implementing hydroacoustic surveys, analyzing, and interpreting EK80 data. Twenty-two participants from ASEAN Member States (AMSs) and SEAFDEC Department (TD, MFRDMD, and IFRDMD) attended the Training. The Training curriculum focused on principle of hydroacoustic survey using the scientific echosounder (EK80) such as acoustic trawl survey, survey design, biomass estimation, and calibration method. Moreover, the calibration of hydroacoustic equipment and basic post-processing such as data analysis using ESP3 software and single target analysis were conducted and practiced. In the end, the participants were expected to comprehensively understand the principle of hydroacoustic survey and data analysis and interpretation using ESP3 and other relevant software through gain practical experience and technical skills that can be applied in future fisheries hydroacoustic survey projects.