Background: In this study it is evaluated whether autogenous bone mixed with biphasic calcium phosphate (BCP) used in a maxillary sinus floor elevation (MSFE) leads to improved bone formation. Materials and methods: In five patients a unilateral MSFE was performed. Histological and histomorphometric analyses were performed on bone biopsies that were obtained 6 months after MSFE during dental implant surgery. Results: The average vital bone volume was 29.9% of the total biopsy (BV/TV, SD±10.1) of which 7.1% was osteoid (OV/BV, SD ± 4.8). The osteoid surface (OS/BS) covered 26.0% (SD ± 13.4) of the bone surface. The BS/TV covered 4.7 mm2/mm3 (SD 2.3). Compared with previous studies the analyses showed a difference for trabecular thickness (Tb. Th.) and osteoid surface (OS/BS), but not for BV/TV, OV/BV and the number of osteoclasts. Conclusion: MSFE with autogenous bone mixed with BCP shows an amount of newly formed bone that is comparable with the findings from the previously published 6-month study with pure BCP. However, a better distribution of the new bone over the entire biopsy was observed.