The utility model discloses a fast assembled large-breadth floor. A back groove is formed in the back of a floor, wherein back grooves of two adjacent floors are connected with each other through an elastic connection part or the two adjacent floors are connected to be a whole body through a groove tenon structure; the fast assembled large-breadth floor is characterized in that a tenon tongue is arranged at one ends of a front end and a rear end of the floor; a tenon groove is formed in the other ends of the front end and the rear end of the floor; a tenon tongue is arranged on one sides of the left side and the right side; a tenon groove is formed in the other sides of the left side and the right side; the two adjacent floors are connected with each other through the groove tenon; a U-shaped elastic sheet inclining inwards is used for clamping and fixing the back grooves of left and right adjacent floors. When one floor needs to be replaced, the sharp end of a disassembling tool is inserted into a structure with the tenon tongue and the tenon groove between the left and right adjacent floors; the force is applied by using the lever principle to squeeze the floor, so that a gap enough for sliding the tenon tongue out of the tenon groove is formed between the adjacent floors; the floor is warped upwards, so that the flexural deformation of the length is implemented; the tenon tongues at the front end and the rear end of the floor fall off from the tenon groove naturally, namely any single floor can be disassembled under the condition without influence on the usage of the adjacent floors.