NOVELTY - A pepper seed oil biodesel is prepared by pre-heating pepper seed oil at 60-70 degrees C in constant-temperature reaction kettle, adding phosphoric acid with amount of 0.2-0.3% of pepper seed oil, stirring at 35-40 degrees C for 20-30 minutes, adding hot water to obtain hydrated colloid, stirring for 15-20 minutes, adding 1.5-2% sodium hydroxide solution to neutralize excess phosphoric acid and to obtain colloid flocculation, continuously stirring for 15-20 minutes, standing at 75 degrees C for 2 hours, centrifuging, washing by water, drying to obtain degummed pepper seed oil, adding alkali liquid, and stirring.    USE - Preparation of pepper seed oil biodesel (claimed).    ADVANTAGE - Process reduces colloid and color, improves pepper seed oil quality, and is simple.    DETAILED DESCRIPTION - A pepper seed oil biodesel is prepared by pre-heating pepper seed oil at 60-70 degrees C in constant-temperature reaction kettle, adding phosphoric acid with amount of 0.2-0.3% of pepper seed oil, stirring at 35-40 degrees C for 20-30 minutes, adding hot water to obtain hydrated colloid, stirring for 15-20 minutes, adding 1.5-2% sodium hydroxide solution to neutralize excess phosphoric acid and to obtain colloid flocculation, continuously stirring for 15-20 minutes, standing at 75 degrees C for 2 hours, centrifuging, washing by water, drying to obtain degummed pepper seed oil, adding alkali liquid, stirring at room temperature, centrifuging to separate liquid oil and liquid soap, repeatedly washing oil with soft water to obtain final oil solution, concentrating to obtain alkali refined pepper seed oil, pre-heating weighed pepper seed oil in 3-necked flask to reaction temperature, adding same amount of methanol concentrated sulfuric acid solution, stirring, transferring reaction product into separatory funnel, standing overnight, transferring upper layer aqueous methanol phase in rotary evaporator, distilling off methanol, standing lower layer esterified oil phase in separatory funnel, washing by water, drying using anhydrous sodium sulfate, and filtering.