Our main aim in this paper is to constrain the effective field theory describing the top quark couplings through the e−e+→tt¯+jet process. The analysis is carried out considering two different center-of-mass energies of 500 and 3000 GeV including a realistic simulation of the detector response and the main sources of background processes. The expected limits at 95\% CL are derived on the new physics couplings such as tt¯γ, tt¯Z, and tt¯g for each benchmark scenario using the dileptonic tt¯ final state. We show that the 95\% CL limits on dimensionless Wilson coefficients c¯i considered in this analysis could be probed down to 10^−4