Abstract: Experiments on extraction of pectin from tobacco dust with an aqueous solution of ammonium iron sulphate and potassium aluminium sulphate were conducted. The conditions for the extraction and precipitation of pectin, such as extraction temperature, extraction duration,water volume added, pH of extract, precipitation temperature, precipitation time, ratio of ammonium iron sulphate to potassium aluminium sulphate, and pH of precipitation were optimized with the orthogonal matrix. The suitable conditions obtained were that 1)temperature, duration, water volume added, and pH for extraction of pectin were 80 to 90℃, one hour, 150ml water, and pH 2.0, and 2)temperature, ratio of salts, duration, and pH for pectin precipitation were 80℃, 2:1, 2 hours, and pH 4.0 respectively. The color of pectin produced under these conditions was better.