The invention discloses a green and environment-friendly 
tenofovir preparation method which comprises the following steps: dissolving a compound I, S-
propylene carbonate and an inorganic 
weak base inan 
organic solvent, reacting for 3-6 hours at 85-120 DEG C, cooling to 
room temperature, and concentrating an obtained 
system under reduced pressure to obtain an intermediate II; dissolving the intermediate II, hydroxymethylphosphonic acid dialkyl ester and trialkyl (
aryl) 
phosphine in an 
organic solvent, stirring at 
room temperature, slowly adding azodicarboxylic acid diester, and reacting for 20minutes to 3 hours to obtain an intermediate III; slowly adding an inorganic strong alkali into the intermediate III, carrying out ice bath, filtering, adjusting the pH value of an obtained filtrate,standing, carrying out suction 
filtration, washing an obtained 
filter cake, and carrying out 
vacuum drying under reduced pressure. According to the method, S-
propylene carbonate, adenine and derivatives thereof are taken as initial raw materials; PMPA is generated through configuration inversion of 
Mitsunobu reaction, the used organic solvents can be recycled, the generated 
wastewater is mainly aharmless inorganic 
salt solution, the cost for further treatment and up-to-standard 
discharge is low, the method is 
environmentally friendly, the reaction is easy to control, the safety is high, andthe comprehensive economic benefit is high.