The invention belongs to the technical field of chemical materials and discloses silver-catalyzed 3-phosphonomethylindoline and a preparation method. N-allyl is used as a novel free radical receptor radical and phosphorylation-arylation reaction is initiated through the novel free radical receptor radical to synthesize 3-phosphonomethylindoline in one step. In the reaction, a non-activated carbon-carbon double bond is used as a novel free radical receptor functional group and H-phosphine oxide is used as a free radical precursor; the silver-catalyzed 3-phosphonomethylindoline has the remarkable advantages of simplicity in operation, low cost, wide substrate range and extremely good exo/endo selectivity; the reaction can be easily amplified and the silver-catalyzed 3-phosphonomethylindolinecan be applied to industrial production.