Energy conservation is a hot topic in the field of construction. To increase the thermal resistance of the enclosing structure of buildings, a T-shaped self thermal insulating block is designed. The particular shape, light weight concrete shell and heat insulating materials filled in the cavities result in a good heat insulating effect. Thermal bridges on the wall can significantly be reduced, which leads to a great improvement in thermal resistance, and performance of energy conservation. The thermal conductivity of wall made of this kind of blocks could be as low as 0.088W/ m·K, by which energy consumption could be saved by 65% comparing with wall made of bricks in 1980s.