Abstract: To achieve targeted utilization efficiency of pesticide in apple trees, the influence of the concentration of EO/PO block polyether-modified silicone adjuvant on the wetting and deposition behavior of sulfoxaflor 22% SC was studied by measuring parameters such as surface tension, contact angle, adhesion tension and the maximum stable retention (R_m), then field trial was conducted. The results showed that the critical micelle concentration (CMC) of EO/PO block polyether-modified silicone was 0.027%, when the added concentration was greater than CMC (0.05%), the surface tension of the sulfoxaflor 22% SC was reduced by 69.61%, the contact angles on adaxial and abaxial surface were decreased by 82.55% and 100%, respectively, the adhesion tension on both surfaces increased from −11.96 mN/m and −44.86 mN/m, respectively, to approximately 21 mN/m. When the added concentration of EO/PO was lower than CMC, the R_m initially increased and then decreased with the increasing adjuvant concentration, reaching a maximum of 19.05 mg/cm² at 0.01%. After exceeding CMC, the R_m declined slightly and entered a plateau phase, but remained significantly higher than that of the control without adjuvant. The results of field trials showed that when 0.05% EO/PO block polyether-modified silicone was added and the usage of pesticide was reduced by 20%, the control efficacy of sulfoxaflor 22% SC against Aphis citricola increased by 17.73% and 10.51% at 3 d and 7 d after treatment, respectively, compared with the treatment without adjuvant and dosage-reduction. In summary, the EO/PO block polyether-modified silicone adjuvant can reduce the surface tension of the pesticide solution, as well as improve the wettability, adhesion and deposition on apple leaves, achieve the effects of reducing dosage while enhancing efficacy.