In order to promote the application and deep research of MgO-admixed concrete, the conditions of concrete deformation, configuration and construction of induced joints for 8 arch dams in Guizhou Province were analyzed. These arch dams were constructed with MgO-admixed concrete in the whole dam body and have been in operation for more than a year. Results show that the statically indeterminate property of the arch dam structure provides a good constrained environment for MgO-admixed concrete to form compressive pre-stresses during the concrete expansion process. The amount of MgO in the concrete can be determined by cement mortar autoclave method or one-grade concrete autoclave method. The measured expansion capacity of dam concrete with such amount of MgO is about 50×10^-6~150×10^-6, which does not reach the expected value to fully compensate the shrinkage crack induced by temperature drop. Configuration of induced joints is an efficient measure to take full advantage of the MgO-admixed concrete damming technology. Once the MgO materials is mixed into the roller compacted concrete(RCC), the fast and economical superiority of RCC and MgO-admixed concrete in dam construction can take great effect.