The aim of this in vitro comparative study was to evaluate and compare the effect of different methods of prophylaxis and conditioning of enamel, in the adhesiveness of a light-curing pit and fissure sealant. The coronal portions of 50 extracted premolars were sectioned into two halves (buccal and lingual) and embedded in acrylic blocks. The samples were divided into five groups according to the methods of prophylaxis: no prophylaxis, pumice powder, chlorhexidine gluconate, fluoridated paste and air prophy; and enamel conditioning techniques: etching with 37 % phosphoric acid and self-etching adhesive. The sealant adhesion strength was measured using an INSTRON machine for a tensile test. The results showed no significant differences in tensile strength according to the enamel conditioning techniques used. Regarding the methods of prophylaxis under study, a significant difference in groups treated with fluoridated paste and air prophy was observed.