Some published articles on the Antarctic krill biomass estimates and ecosystem models by Japanese scientists were reviewed. The concept and treatment of Lotka-Volterra type model by Yamanaka (1983) and Nagata (1983) were compared and some future modifications were discussed. While a network model such as developed by Doi (1879) is able to deal with many components in the Antarctic eco­system simultaneously, it was felt a further review was needed to develop this model.