Lengthened linear sliding rail capable of being spliced at high precision

The utility model relates to a lengthened linear sliding rail capable of being spliced with high precision. The linear track comprises a linear track body, the linear track body comprises a top face, two side faces, two end faces and a bottom face, ball grooves distributed in the length direction of the two side faces are symmetrically formed in the two side faces, a plurality of first counter bores penetrating through the bottom face are formed in the top face, guide grooves are formed in the two ends of at least one of the top face, the bottom face and the two side faces, and the guide grooves are communicated with the end faces. The linear track body further comprises a guide block matched with the guide groove in appearance, a screw hole is formed in the guide groove, and a second counter bore is formed in the guide block. The guide block can be matched with the two guide grooves of the two linear track bodies at the same time, after the guide block and the two guide grooves are completely fixed, the end