Biodiesel is one of the paramount biofuels and alternates for geologically produced petroleum fuel. The lipid sources in dissipate material are very much valuable in two ways: one is for the remediation of dissipate and the other is to obtain a high percentage of biofuel. Hence, in the present study Solanum nigrum L. seed - a widespread weed found in agricultural fields - was selected as a source to produce biodiesel via the transesterification process with the help of an alkali catalyst. The highest conversion of Solanumnigrum L. seed oil (as triglyceride) to biodiesel was achieved as 99.6 wt% with 35 min reaction time at 65 degrees C, 9: 1 molar ratio of methanol to oil, and 1 wt% of potassium hydroxide (KOH) catalyst. At the optimized condition, the conversion of triglyceride to biodiesel was confirmed by H-1 NMR and the fuel properties of biodiesel were analyzed. The fuel properties were originated to be observed within the limit of ASTM D6751 standard.