The invention provides a foam concrete composite heat preservation wall body with concrete blocks, belonging to the field of building energy conservation. The foam concrete composite heat preservation wall body is used for buildings, such as dwellings, workshops, hotels and the like, and is particularly suitable for new rural reconstruction. The wall body provided by the invention is prepared by constructing different combinations of five concrete precast blocks with different shapes with cement mortar. According to a quantity of floors, the wall body is reinforced, and a wall post and a ring beam can be borne by using wall body reinforcing ribs with different quantities, different manners and different specifications. Ordinary concrete is cast at positions of posts and beams in the hollow wall body, and foam concrete with a concentration of 200-400 kg/m<3> is cast at the other positions, so as to form the heat preservation and sound insulation wall body, and carry out mortar plastering and decoration. When the wall body provided by the invention is more than or equal to 250 mm thick, an average volume weight of the wall body is less than or equal to 600 kg/m<3>, a heat conduction coefficient is less than or equal to 0.4 W/(m2.K), and a pressure-resistant strength of a wall surface is more than or equal to 20 MPa. The wall body provided by the invention has the advantages of convenience and rapidness of construction. Furthermore, the wall body is firm, durable, mild, environment-friendly and safe.