THK N_2O is an important greenhouse gas. In the steady state the stable isotopic composition of nitrogenand oxygen in tropospheric N_2O is balanced by isotopically light N_2O emitted from soils and oceans andisotopically heavy N_2O as return flux from the stratosphere. However, no such balance was reached incalculations given by Kim and Craig. This serious discrepancy lied in the fact that only soil and oceanic sources were considered in Kim and Craig’s calculation and N_2O emission from tropical forest soil wastaken as the global soil contribution. Progress since the 1990s in identifying additional sources of atmospheric N_2O as well as in the estimation from various types of soil allows us to make more realistic assessment of nitrogen and oxygen isotope balance budgets in tropospheric N_2O. In this note, modification willbe proposed of atmospheric N_2O nitrogen and oxygen isotope budgets to Kim and Craig’s calculation. The static balance of nitrogen and oxygen isotopes in tropospheric N_2O is expressed by THK N_2O is an important greenhouse gas. In the steady state the stable isotopic composition of nitrogen and oxygen in tropospheric N_2O is balanced by isotopically light N_2O emitted from soils and oceans and isotopically heavy N_2O as return flux from the stratosphere. However, no such balance was reached This serious discrepancy lied in the fact that only soil and oceanic sources were considered in Kim and Craig’s calculation and N_2O emission from tropical forest soil wastaken as the global soil contribution. Progress since the 1990s in identifying additional sources of atmospheric N_2O as well as in the estimation from various types of soil allows us to make more realistic assessment of nitrogen and oxygen isotope balance budgets in tropospheric N_2O. In this note, modification will be proposed of atmospheric N_2O nitrogen and oxygen isotope budgets to Kim and Craig’s The static balance of nitrogen and oxygen isotopes in tropospheri c N_2O is expressed by