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The heterogeneous catalysis of African pear seed oil (APO) and modelling of some thermo-physical properties of the biodiesel was carried out. The oil was extracted with petroleum ether solvent and characterized with Association of Analytical Chemist (AOAC). The catalysts were synthesized by thermal, acid and alkaline activation of clay. The catalysts were characterized and used to transesterify the APO. The biodiesel produced were characterized using American Society for Testing Materials ASTM D6571 and some the thermo-physical properties such as density, kinematic viscosity and cetane number were modelled using multilinear regression analysis of Polymath version 5.0. The 52% yield of oil from the African pear seeds using the petroleum ether was comparable with yields obtained from other nonedible seeds. The transesterification of the oil was significantly affected by increase in process variables but the yield of methyl ester decreased beyond 3 h reaction time, 3 wt% catalyst concentration, 10:1 methanol/oil molar ratio, 60 oC reaction temperature and 300 rpm agitation speed. The physicochemical properties of the biodiesel produced meet the ASTM standard and were within the acceptable limits. The biodiesel produced via transesterification of APO using thermally, acid and alkaline activated catalyst have similar properties and can be blended to form a homogeneous fuel. The coefficients of determination are close to 1 while the root mean square value is less than 0.2. This shows that the multilinear regression can model the thermo-physical properties of the biodiesel.