The utility model discloses a side overlapping structure and a body in white of a vehicle as well as the vehicle. The side overlapping structure comprises a first side surrounding panel, a second side surrounding panel and a reinforcing inner panel; the first side surrounding plate comprises a first side surrounding panel body and a first bending part formed in such a way that the first side surrounding board body is bent and extends; the second side surrounding panel comprises a second side surrounding panel body and a second bending part formed in such a way that the second side surrounding panel body is bent and extends; the side surface of the first bending part is fixedly connected with the side surface of the second bending part; a continuous extending side surface is formed by the first side surrounding panel body and the second side surrounding panel body; the reinforcing inner panel comprises a reinforcing inner panel body and a third bending part formed in such a way that the reinforcing inner panel body is bent and extends; the reinforcing inner panel body is connected to the second side surrounding panel body; the third bending part is fixed on the side surface, back to the first bending part, of the second bending part. According to the scheme, the welding cost of the side surrounding panels can be reduced, the appearance defects of the side surrounding panels are avoided, and the manufacturing process and the manufacturing time of the side surrounding panels are reduced.