Method for real-time regulation of the operation of at least one catalyst of exhaust gases produced by a heat engine equipping a motor vehicle, the method implementing a control-command device comprising a system for analyzing in real time the operation of the catalyst and at least one regulator of an air intake into the exhaust gases upstream of the catalyst, the implementation of the regulator being placed under dependence on an activation order emitted by the analysis system in the event of detection of an oxygen richness error in the exhaust gases upstream of the catalyst, said oxygen error being detected from a logical processing by the analysis system of measurements (M1, M2) respectively provided by voltaic oxygen probes (8a, 8b) placed on an exhaust line of the exhaust gases, including a proportional upstream probe and a binary downstream probe respectively placed upstream and downstream of the catalyst, characterized: in that said oxygen richness error is identified after a proportional-integral correction of the measurements provided by the downstream probe which is carried out by an integrator which the analysis system comprises, and in that the activation of the integrator is conditioned at least as a dependency of the validation: -) of a first parameter relating to an error convergence of the oxygen richness of the exhaust gases measured upstream of the catalyst by the upstream probe with respect to a predefined error threshold, and -) of a second parameter relating to a detection of a stable operating state of the catalyst over a predefined duration. the implementation of the regulator being placed under dependence on an activation order emitted by the analysis system in the event of detection of an oxygen richness error in the exhaust gases upstream of the catalyst, said oxygen error being detected from a logical processing by the analysis system of measurements (M1, M2) respectively provided by voltaic oxygen probes (8a, 8b) placed on an exhaust line of the exhaust gases, including a proportional upstream probe and a binary downstream probe respectively placed upstream and downstream of the catalyst, characterized: in that said oxygen richness error is identified after a proportional-integral correction of the measurements provided by the downstream probe which is carried out by an integrator which the analysis system comprises, and in that the activation of the integrator is conditioned at least as a dependency of the validation: -) of a first parameter relating to an error convergence of the oxygen richness of the exhaust gases measured upstream of the catalyst by the upstream probe with respect to a predefined error threshold, and -) of a second parameter relating to a detection of a stable operating state of the catalyst over a predefined duration. in that said oxygen richness error is identified after a proportional-integral correction of the measurements provided by the downstream probe which is carried out by an integrator which the analysis system comprises, and in that the activation of the integrator is conditioned at least as a dependency of the validation: -) of a first parameter relating to an error convergence of the oxygen richness of the exhaust gases measured upstream of the catalyst by the upstream probe with respect to a predefined error threshold, and -) of a second parameter relating to a detection of a stable operating state of the catalyst over a predefined duration. -) of a first parameter relating to an error convergence of the oxygen richness of the exhaust gases measured upstream of the catalyst by the upstream probe with respect to a predefined error threshold, and -) of a second parameter relating to a detection of a stable operating state of the catalyst over a predefined duration.