Disclosed is a flexible surgical instrument system with a prepositioned drive input, the flexible surgical instrument system comprising a flexible continuous body structure (10) and a driving unit (20). The flexible continuous body structure (10) comprises a distal structural body (101), a proximal structural body (102) and a middle connecting body (103). The distal structural body (101) comprises at least one distal structural segment (104, 105). The distal structural segment (104, 105) comprises distal spacing disks (106), a distal fixing disk (107) and structural backbones (108). The proximal structural body (102) comprises proximal structural segments (109, 110) having the same number as the number of distal structural segments (104, 105). The proximal structural segment (119, 110) comprises proximal spacing disks (111), a proximal fixing disk (112) and structural backbones (108). The middle connecting body (103) comprises two channel fixing plates (113), and a structural backbone guide channel (114) provided between the two channel fixing plates (113). The driving unit (20) comprises a driving unit fixing plate (201) provided in front of the middle connecting body (103). A plurality of linear motion mechanisms (202) for converting a rotary input from a motor into a linear motion output are provided between the driving unit fixing plate (201) and the channel fixing plate (113). Output ends of the linear motion mechanisms (202) are connected to one end of a driving backbone (203), the driving backbone (203) passes through the proximal spacing disks (111), and the other end of the driving backbone is securely connected to the proximal fixing disk (112).
