Purpose: This study evaluated the effect of low-level laser therapy (LLLT) on the healing of bone defects filled with autogenous bone or bioactive glass. Materials and Methods: A critical size defect with 5-mm diameter was created on the calvaria of 60 adult male rats divided into 6 groups (n = 10): group C (control), group LLLT (LLLT - GaAlAs, wavelength of 780 nm, power of 100 mW, energy density of 210 J/cm2 per point during 60 seconds/ point, in five points, only once, after creation of the surgical defect), group AB (autogenous bone), group AB+LLLT (autogenous bone + LLLT), group BG (bioactive glass), group BG+LLLT (bioactive glass + LLLT). All animals were sacrificed at 30 days after surgery. The areas of newly formed bone (ANFB) and areas of remaining particles (ARP) were calculated in relation to the total area (TA). Results: The highest mean ± SD ANFB was observed for group LLLT (47.67% ± 8.66%), followed by groups AB+LLLT (30.98% ± 16.59%) and BG+LLLT (31.13% ± 16.98%). There was a statistically significant difference in relation to ANFB between group C and the other groups, except for comparison with group BG (Tukey test, P > .05). There was no statistically significant difference in ANFB values between group AB and the other study groups (Tukey test, P > .05), group AB+LLLT and groups BG and BG+LLLT (Tukey test, P > .05), and between groups BG and BG+LLLT (Tukey test, P > .05). The highest mean ± SD ARP was found for group BG (25.15% ± 4.82%), followed by group BG+LLLT (17.06% ± 9.01%), and there was no significant difference between groups (t test, P > .05). Conclusion: The LLLT, in the present application protocol, did not increase the area of new bone formation when associated with autogenous bone or bioactive glass. Keywords: biomaterials, bone substitute, lasers