Gender is a socially constructed definition of women and men. It is not the same as sex (biological characteristics of women and men). It determined by the conception of tasks, functions and roles attributed to women and men in the society, in public and personal life, The Southeast Asian Fisheries Development Center (SEAFDEC) recognized that gender issue is an important approach to make happiness of work and try to mainstream it to organization and programs/projects. In term of gender, the first step to mainstream gender into organization should be that all staff must understand on gender concept. Therefore, Gender Sensitivity training course was conducted from 4 April to 1 May 2017 with total of for all SEAFDEC during 4 to 5 April and 1 of May with total 93 of SEAFDEC staffs from Training Department and secretariat who participated in the training. The objectives are to provide knowledge on gender and understand why we need to integrate gender in to organization and raise the gender awareness on gender equality is very important in our organization because it gives equal enjoyment for women and men of sociality-valued goods, opportunities, resources and reward. It doesn’t mean that both are equal but their opportunities and life chances are equal. This showed that SEADFE is gender responsive organization and used to integrate gender in projects/programs as well as also concerned gender issue in the organization.