Various synthetic bone substitutes have been developed to reconstruct the bony defects that clinicians often encounter during surgical procedures. Among various synthetic bone substitutes, calcium phosphate (Ca-P) ceramics have been investigated because their composition and structure are similar to those of human bone. We evaluated the bone healing and biodegradation patterns of three types of Ca-P ceramic particle with various hydroxyapatite (HA)/β-tricalcium phosphate (β-TCP) weight ratio: pure β-TCP, biphasic Ca-P (BCP) with a HA/β-TCP weight ratio of 60/40 (BCP 60/40), and BCP with an HA/β-TCP weight ratio of 20/80 (BCP 20/80). Four 8-mm-diameter defects were created in ten rabbits. Three of the defects in each rabbit were separately and randomly filled with one of the three experimental Ca-P ceramic particles, and the fourth was filled with blood clots (control). The specimens were harvested at 2 and 8 weeks post-surgery. The histologic and histometric findings revealed that the augmented space and new bone formation were significantly better for all three Ca-P ceramics than for the control group at both 2 and 8 weeks (p < 0.05). Compared to the pure β-TCP, the two BCP groups were found to provide a larger amount of newly formed bone and bone density at the 2- and 8-week post-operative periods (p < 0.05). Throughout the observation period, BCP 60/40 and BCP 20/80 exhibited a similar bone healing and biodegradation patterns with regard to both individual particles and the total augmented area in vivo. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 80–88, 2014.