A guidewire-guiding device, and guidewire-guiding assembly. The device comprises a main guidewire channel (2) and guidewire-guiding channels (3) are respectively arranged in the guiding body (1). The main guidewire channel (2) and the guidewire-guiding channels (3) respectively pass through the guiding body (1) along an axial direction, and in-vivo end openings of the guidewire-guiding channels (3) and the in-vivo end opening of the main guidewire channel (2) are arranged along the axial direction at intervals. the guiding body (1) may be imbedded into a blood vessel in vivo via the main guidewire (4) penetrating through the main guidewire channel (2), and as the in-vivo end openings of the guidewire-guiding channels (3) are arranged along the axial direction at intervals, the to-be-guided guidewires enter the guidewire-guiding channels (3) while being staggered to the main guidewire (4) on the axial direction, therefore the problem of tanglement of the main guidewire (4), the branch guidewires (6) and other kinds of guidewires may be avoided.
