The invention belongs to the technical field of agricultural mechanized transplantation, and particularly relates to a seedling sending, taking and delivering device for a pressing type seedling taking full-automatic seed tray seedling transplanter. The device comprises a rack, a seedling sending mechanism and a seedling taking and delivering mechanism; the seedling sending mechanism comprises a lead screw driving motor, a chain driving motor, a sliding rail, a side plate, a chain, a front bottom plate, a driven shaft, a driving shaft, a rear sliding rail support, a sliding rail sliding block,a rear bottom plate, a first connecting beam, a ball lead screw, a lead screw sliding block, a second connecting beam, a third connecting beam and a front sliding rail support; the seedling taking and delivering mechanism comprises a seedling taking plate, a cylinder mounting plate, a seedling pressing rod, a seedling pressing cylinder and a seedling guide tube. Accordingly, pot seedlings are taken out from the lower portion of a seedling tray, seedling delivering is conducted directly, and the seedling taking process and the seedling delivering process are combined into a whole, and the efficiency is higher.