There are three emperor penguin breeding colonies located along the coast of Northern Victoria Land, Ross Sea. KOPRI conducted a population monitoring survey on three of emperor penguin colonies, Cape Washington (ASPA No. 173), Coulman Island and Cape Roget. The colony of Cape Roget was surveyed by researchers for the first time in November 2021. The emperor penguin chick counting on Cape Washington was conducted seven times during austral summer seasons from 2014 to 2021. And we surveyed colony of Coulman Island, one of the largest colonies in Antarctica, four times from 2017 to 2021. We visited on the ground and counted chicks by researchers in November 2014 and December 2015, while we used aerial photograph to determine the colony size of emperor penguins from 2016. We could not visit the colonies of Cape Washington and Coulman Island in 2020, because field activities were cancelled due to the pandemic situation of covid-19 worldwide.