At the end of COP26, Vietnam has developed many institutions and policies to fulfill its commitment to bring net emissions to “zero” by 2050 and reduce methane (CH4) to at least 30% by 2020 in 2030. In order to gradually achieve the above goal, an inventory of facilities with greenhouse gas emissions plays a very important role. This study was conducted to estimate greenhouse gas emissions at seafood export processing factory. The study was carried out based on the method of collecting data from different emission sources and calculating emissions based on activity data and emission factors from reliable sources. The research results show that, during the study period from March 2022 to March 2023, the total emissions at the facility were 19,144.14 tons of CO2eq, of which indirect emissions from waste and electricity accounted for the high rate is about 60.37% and 36.55% of the total CO2eq, respectively. Research results also show that CO2 is the most emitted gas into the environment and is present in most of the waste sources. In which, electricity consumption and CO2 emissions are the most significant, indirectly emitting 7,102.85 tons of CO2/year (accounting for 98.51% of total waste sources). For daily waste, landfilling indirectly release into the atmosphere an amount of methane (CH4) approximately 410 tons/year, accounting for more than 95% of the total emissions. In addition, in the process of using fuel (gasoline and DO) at the facility, a large amount of N2O gas enters the atmosphere (nearly 70% of emissions from DO and 30% from gasoline). Reduction of greenhouse gas emissions at the facility could be achieved by saving water, reducing wastewater and using clean energy.