The invention discloses a sand washing type fishing technology for a sand prevention pipe string, which comprises the steps of 1) cutting off a blind pipe of a top sand prevention pipe section; 2) recovering a top packer; 3) running a sand washing pipe string into the residual sand prevention pipe string of the top sand prevention pipe section; 4) slowly putting down the sand washing pipe string, and simultaneously, circulating washing liquid to conduct sand washing for annular space between the top sand prevention pipe section and a casing pipe; 5) cutting off a blind pipe which is close to the lower portion of an intermediate isolation packer on the top currently; 6) fishing the residual sand prevention pipe string of the top sand prevention pipe section and an intermediate isolation packer at the bottom of the top sand prevention pipe section; and 7) repeating steps 3) -6) to fish out the residual sand prevention pipe string of the next sand prevention pipe section and an intermediate isolation packer at the bottom of the next sand prevention pipe section until all the sand prevention pipe sections and packers are fished out. The sand washing type fishing technology can solve the problem that conventional casing milling is difficult to adopt due to the small annular space between a screen pipe and the casing pipe, effectively speed up the fishing schedule, accelerate the operation effectiveness for a given period of time, control the expenses in a work period and save the operation cost.