Biodiversity loss has become a major problem in Southwestern Nigeria because 70-80 % of its forest has been converted to non-forest uses. Modern conservation systems have not yielded desired result because the techniques had proved inadequate in addressing conservation issues. This calls for an integration of indigenous conservation techniques with aspects of the modern techniques. The study is a comparative analysis of indigenous and modern methods of forest management in Southwestern, Nigeria. The objectives were to: (i) determine the level of adoption on indigenous and modern knowledge system of forest biodiversity conservation methods in the study area; (ii) assess the impact of indigenous and modern forest conservation; (iii) identify the factors affecting forest biodiversity conservation; and (iv) assess peopleâ€™s perception of the relative effectiveness of indigenous and modern methods of forest biodiversity conservation in the study area.rnPrimary and secondary data were used in this study. Primary data were collected through questionnaire administration and Focus Group Discussions (FGDs). The secondary data (inventories of woody species, lists of communities within the buffer zone, types of forest resources and conservation techniques) were obtained from Osun Osogbo Grove (OOG) and Old Oyo National Park (OONP) records. Nine communities that fell within 0-10km around the OONP were randomly selected, while the four communities surrounding the OOG were sampled. In all, 539 copies of the questionnaire were administered. Quadrant method was used for sampling of the woody species. The study sites consisted of eight plots of 50 x 50 m along two 300m long transects. One Way ANOVA, Discriminant Analysis, Relative Species Index, Species Diversity Index (SDI), Important Value Index and some descriptive methods, such as; tabulation, percentages, mean and standard deviation were used to analyse the data.rnThe findings of the study were that:rni) 96.1%, 97.5% and 90.9% of residents, stakeholders and staff, respectively supported the adoption of indigenous methods in OOG, while, 90.1%, 92.6% and 87.8 % of the residents, stakeholders and staff, supported the adoption of modern approaches in forest management in OONP;rnii) biodiversity index was higher under indigenous conservation method at OOG of (3.48) compared to OONP (3.14) under modern conservation method;rniii) factors affecting bio-diversity conservation in the two sites were fuel wood collection(19.60%),farming(21.50%),bush burning(17.83%), pastoralism (12.77%), deforestation(14.70%) and national policy governing the protected areas(13.60%);rniv) 85% of the respondents viewed indigenous knowledge system as an effective conservation method; andrnviiirnv) the Species Diversity Index (SDI) suggests that both indigenous and modern techniques of forest conservation encouraged biodiversity conservation (SDI 3.01- 8.27);rnThis study concluded that indigenous conservation techniques yielded better conservation results than modern techniques. The study recommended that indigenous conservation techniques should be given priority over modern techniques and where necessary both should be integrated.