To provide a laminated lumber, which has a strength enough to overcome a tensile stress and an extremely high reliability.

Connected lumbers 2, 3 and 4, each of which is produced by connecting a plurality of rectangular lumbers in their longitudinal direction, are laminatedly bonded in the direction of the thickness of the connected lumbers 2, 3 and 4 so as to form a laminated lumber 1. A joint part 19 in the longitudinal direction of one and the other rectangular lumbers 9 and 10, which connect with each other and at least compose the connected lumber 4 locating at the lowermost stage of the laminated lumber is equipped with one joint worked part 17 having one come-off preventive engaging surface 17d projecting from one end of one rectangular lumber 9 and the other joint worked part 18, which is formed at the other end of the other rectangular lumber connecting in the longitudinal direction of the one rectangular lumber 9 and has the other engaging surface 18d engaging with the one engaging surface 17d. In this case, the one joint worked part 17 is fitted to the other joint worked part 18 so as to engage the one engaging surface 17d with the other engaging surface 18d.