Objectives: The aim of this in vitro study was to evaluate the microtensile bond strength of three self-etching adhesive systems- Tyrian/One Step (Group A), Clearfil SE Bond (Group B), and Prime & Bond NT/NRC (Group C)- and the morphology, by SEM, of their adhesive/dentine interfaces. Methods: A flat dentin surface was exposed in 24 human third molars, the adhesive systems were applied according to the manufacturer's instructions, and composite resine crowns (Z-250) were built incrementally. Specimens were stored for 24h at 37°C and longitudinally sectioned in both the “x” and “y” directions to obtain sticks with a cross-sectioned area of 0.8mm2 (±0.2). The specimens were tested in a tensile load machine (0.05 mm/min). Data were statistically analysed by ANOVA and Tukey test (p<0.05). For SEM, it were employed 3 molars for each group. The adhesive interfaces were sectioned, flattened, polished, and prepared for SEM. Results: Means (MPa) of microtensile bond strength test were: Group A- 22.26 (±4.76); Group B- 34.47 (±5.44); Group C- 31.47 (±7.76). It was not observed difference between Groups B and C, however, they were different to Group A. SEM- The analysis of the eletromicrographs revealed homogeneous hybrid layer and uniform and conical tags for all groups. Conclusion: It may be concluded that the adhesive systems Clearfil SE Bond and Prime & Bond NT/NRC presented superior microtensile bond strength, and the morphology of their adhesive interfaces were similar to the interface promoted by Tyrian/ One Step.