NOVELTY - Production of Adefovir comprises: (a) suspending 1000-3000 mol of paraformaldehyde in 1000-3000 mol of 2-chloroethanol, reducing the temperature to less than 10 degrees C and introducing dry hydrochloric acid gas until the paraformaldehyde is completely dissolved; (b) placing 500-2000 mol of 1-chloro-2chloromethoxyethane into a reactor and heating; (c) adding 500-1200 mol of adenine and 1005-2412 mol of alkaline catalyst; (d) adding 50-100 kg of 9-(2-isopropoxy phosphonomethoxy)ethyl adenine and 5-20 kg of catalyst; and (e) separating and purifying the product of (d) to obtain the refined Adefovir.    USE - The process is useful for producing Adefovir (claimed).    ADVANTAGE - The process is simple in technique, easy in operation, safe, and environment-friendly. Moreover, the most basic raw materials and regular reagents are used under moderate reaction conditions; thus, the cost is low while the purity of the products is high. Additionally, it is easy to industrialize.    DETAILED DESCRIPTION - Production of Adefovir comprises: (a) suspending 1000-3000 mol of paraformaldehyde in 1000-3000 mol of 2-chloroethanol, reducing the temperature to less than 10 degrees C and introducing dry hydrochloric acid (HCl) gas until the paraformaldehyde is completely dissolved; standing the solution to separate the layers; adding anhydrous sodium sulfate to the organic layer to dry the layer and staying it for a night; distilling under a reduced pressure and collecting the 78-84 degrees C/10.64 kPa fractions to obtain colorless 1-chloro-2chloromethoxyethane solution; (b) placing 500-2000 mol of 1-chloro-2chloromethoxyethane into a reactor and heating at 85-95 degrees C; dripping 550-2200 mol of triisopropyl phosphate for 2.5-3 hours and heating the solution at 125-130 degrees C until 1-chloro-2chloromethoxyethane finishes the reaction to obtain a yellow liquid; distilling under a reduced pressure and collecting the 160-175 degrees C/10.64 kPa fractions to obtain an intermediate body, 2-chloroethyoxyl isopropyl methylphosphonate; (c) adding 500-1200 mol of adenine and 1005-2412 mol of alkaline catalyst to 600-1500 L of a polar non-protonic organic solvent with a boiling point higher than 110 degrees C; increasing the temperature to 100-110 degrees C and dripping in 575-1380 mol of 2-chloroethyoxyl isopropyl methylphosphonate to react for 5-8 hours; after the adenine completely reacts, distilling the system under a reduced pressure and recycling the organic solvent; cooling the system at room temperature and adding dichloromethane for refluxing extraction to collection the organic layer; evaporating the solvent and recrystallizing to obtain white crystal of 9-(2-isopropoxy phosphonomethoxy)ethyl adenine; (d) adding 50-100 kg of 9-(2-isopropoxy phosphonomethoxy)ethyl adenine and 5-20 kg of catalyst to 200-350 kg of the polar non-protonic organic solvent; dripping in 60-130 kg of trimethyl chlorosilane and immediately increasing the temperature to the refluxing temperature for 5-7 hours of reaction; after the raw materials finish reaction, distilling the system under a reduced pressure and recycling the solvent to obtain a product containing Adefovir; and (e) separating and purifying the product of (d) to obtain the refined Adefovir.