Hydrogen sulfide(H2S)is a newly-discovered gaseous signalling molecule and involved in ethylene and ABA induced stomatal closure.Extracellular ATP(eATP)is another new factor participated in regulation of stomatal closing.However,the mechanism of how H2S promotes stomatal closing remains unclear.Here we employed Arabidopsis wild type and mutant lines of ATP Binding Cassette Transporters(Atmrp4,Atmrp5 and their double mutant Atmrp4/5)to study the function of eATP in H2Sregulated stomatal movement.Our results indicated that H2S causes stomatal closing through stimulating guard cell outward K+current.Moreover,we found that H2S induced eATP generation by regulating the activity of an ABC transporter.The inhibitor of ABC transporters,glibenclamide(Gli),impaired H2S promoted stomatal closure,and H2S-dependent eATP accumulation also decreased in Atmrp4 and Atmrp5 mutants.In addition,H2S promotion on outward K+currents was diminished in the Atmrp4/5 double mutant.Our data further suggested that H2O2 is also required in H2Sinduced stomatal closure,and the production of H2O2 is regulated by eATP via NADPH.In summary,current work strongly indicated that H2S-induced stomatal closure requires ABC transporter-dependent eATP production and subsequent NADPH-dependent H2O2 accumulation.