We aimed to evaluate the microtensile bond strength (µTBS) of experimentally developed all-in-one adhesives containing surface reaction-type pre-reacted glass-ionomer (S-PRG) filler as a direct pulp-capping agent. Flattened dentin surfaces of extracted human molars were treated with four experimental adhesives of different S-PRG filler content (group 1: 0 wt%, group 2: 13 wt%, group 3: 27 wt% and group 4: 40 wt%) and Fluorobond Shakeone as the control. The beam samples were made and attached to the testing device, placed onto the tabletop-material-tester, and subjected to µTBS test. The data were statistically analyzed using one-way ANOVA. The results demonstrated that the µTBS value of group 2 was significantly lower than that of the control. No other significant differences among the µTBS values of groups and control were observed. It was concluded that the µTBS values of the experimental adhesives were not affected by the S-PRG filler contents except in group 2.