NOVELTY - Preparing complex microbial organic fertilizer involves filtering sugar refinery waste liquid with filter cloth to obtain filtrate that is aerated for 2 hours. The aerated filtrate is mixed with trace metal liquid, lactic acid solution (25%) and Stenotrophomonas maltophilia nutrient solution for 15 minutes to obtain liquid mixture that is aerated for 6 hours. Micro metal liquid comprises cobalt chloride hexahydrate, copper chloride, boric acid, manganese chloride tetrahydrate, sodium molybdate dihydrtae, nickel chloride and zinc chloride.    USE - Method for preparing complex microbial organic fertilizer used for improving land (claimed).    ADVANTAGE - The method enables to prepare complex microbial organic fertilizer reduces salinity and alkalinity, and releases nitrogen, phosphorus and potassium.    DETAILED DESCRIPTION - Preparing complex microbial organic fertilizer involves filtering sugar refinery waste liquid with filter cloth to obtain filtrate that is aerated for 2 hours. The aerated filtrate is mixed with trace metal liquid, lactic acid solution (25%) and Stenotrophomonas maltophilia nutrient solution for 15 minutes to obtain liquid mixture that is aerated for 6 hours. Micro metal liquid comprises cobalt chloride hexahydrate, copper chloride, boric acid, manganese chloride tetrahydrate, sodium molybdate dihydrtae, nickel chloride and zinc chloride. Stenotrophomonas maltophilia nutrient solution comprises maltose, ammonium chloride, monopotassium phosphate, magnesium chloride and calcium chloride dihydrtae. Ammonium phosphate solution is slowly dripped in aerated liquid mixture to obtain mixed liquid that is processed with concentrated sulfuric acid, sodium hydroxide and hydrochloric acid to obtain another liquid mixture. The liquid mixture is treated with calcium disodium ethylenediamine tetraacetate solution to obtain mixed liquid that is further treated with formaldehyde water solution, sodium hydroxide, hydrochloric acid, deionized water, calcium nitrate and sodium alginate solution. The obtained liquid mixture is heated at 75 degrees C to obtain solid granule that is washed with deionized water to obtain solid particle. The solid particle is mixed with obtained liquid mixture to obtain suspension as product.