A flexible surgical instrument system, comprising a flexible surgical instrument and a driving unit, the flexible surgical instrument comprises a flexible continuous body structure composed of a distal structural body, a proximal structural body and a middle connecting body; the distal structural body comprises at least one distal segment (12,13) comprising a distal spacing disk (121,131), a distal fixation disk (122,132) and structural backbones (123,133); the proximal structural body comprises at least one proximal segment (17,18) comprising a proximal spacing disk (171,181), a proximal fixation disk (172,182) and structural backbones (173,183); the middle connecting body comprises a proximal channel fixing plate, a distal channel fixing plate and a structural backbone guide channel provided between the proximal channel fixing plate and the distal channel fixing plate; wherein the structural backbones (123,133) of the distal segment (12,13) are securely connected in one-to-one correspondence to or are the same as the structural backbones (173,183) of the proximal segment (17,18), one end of each of the structural backbones (173,183) is securely connected to the proximal fixation disk (172,182), and the other end of the structural backbones (173,183) passes through the proximal spacing disk (171,181), the structural backbone guide channel, and the distal spacing disk (121,131) in sequence, and is securely connected to the distal fixation disk (122,132); and the driving unit comprises a driving unit fixing plate, a plurality of linear motion mechanisms for converting a rotational motion input into a linear motion output are provided between the driving unit fixing plate and the distal channel fixing plate, an output end of each of the linear motion mechanisms is securely connected to a corresponding first driving backbone, one end of the first driving backbone is securely connected to one end of a second driving backbone via an adapter unit, and both the other end of the first driving backbone and the other end of the second driving backbone pass through the proximal spacing disk (171,181) and are then securely connected to the proximal fixation disk (172,182); the linear motion mechanism comprises a first lead screw, a first sliding block and a first shaft, the first sliding block is slidably connected to the first shaft and is threadly connected to the first lead screw; and the first driving backbone is securely connected to the first sliding block; the adapter unit comprises a routing backbone, structural backbone connectors, and each of two ends of the routing backbone is securely connected to one of the structural backbone connectors, wherein one of the structural backbone connectors is securely connected to one end of the first driving backbone, and another structural backbone connector is securely connected to one end of the second driving backbone. the structural backbones (123,133) of the distal segment (12,13) are securely connected in one-to-one correspondence to or are the same as the structural backbones (173,183) of the proximal segment (17,18), one end of each of the structural backbones (173,183) is securely connected to the proximal fixation disk (172,182), and the other end of the structural backbones (173,183) passes through the proximal spacing disk (171,181), the structural backbone guide channel, and the distal spacing disk (121,131) in sequence, and is securely connected to the distal fixation disk (122,132); and the driving unit comprises a driving unit fixing plate, a plurality of linear motion mechanisms for converting a rotational motion input into a linear motion output are provided between the driving unit fixing plate and the distal channel fixing plate, an output end of each of the linear motion mechanisms is securely connected to a corresponding first driving backbone, one end of the first driving backbone is securely connected to one end of a second driving backbone via an adapter unit, and both the other end of the first driving backbone and the other end of the second driving backbone pass through the proximal spacing disk (171,181) and are then securely connected to the proximal fixation disk (172,182); the linear motion mechanism comprises a first lead screw, a first sliding block and a first shaft, the first sliding block is slidably connected to the first shaft and is threadly connected to the first lead screw; and the first driving backbone is securely connected to the first sliding block; the adapter unit comprises a routing backbone, structural backbone connectors, and each of two ends of the routing backbone is securely connected to one of the structural backbone connectors, wherein one of the structural backbone connectors is securely connected to one end of the first driving backbone, and another structural backbone connector is securely connected to one end of the second driving backbone.