Aim: To comparatively evaluate the regeneration potential of Hydroxyapatite β- tricalcium phosphate and autogenous bone graft in the treatment of periodontal intrabony defects. Material and Methods: A total of 20 sites were selected from those attending the Out Patient Department (OPD) of Department of Periodontology and oral implantology at Swami Devi Dyal Dental College and Hospital, Barwala, Panchkula. Subjects for the study were selected randomly with no discrimination on the basis of sex, caste, religion or socioeconomic status. Complete medical and dental history was obtained. A complete clinical and radiographic evaluation was performed. Patients who were diagnosed as suffering from moderate to advanced periodontitis along with radiographic evidence of periodontal osseous defects were selected for the study. Results: The results were compiled and statistically analysed using paired T- test. The data was normally distributed and it was analysed by paired T-test. Analysis of the data was done in two parts: inter group and intra group analysis. Intra group comparision shows significant differences at 3 months and 6months (p>0.001) but intergroup comparison shows non significant comparision. (p<0.001) Conclusions: The results of the present study showed that all the graft material resulted in increased bone levels, increased attachment level, reduced probing depth, significant bone resolution.