A self-circulated compounding reactor relates to a chemical synthesis reactor. The utility model is mainly composed of a reaction chamber, an upper gas chamber, a cooling coil, a descending channel, a lower gas chamber and a shell. The upper gas chamber is above the reaction chamber and the lower chamber is a lower gas chamber. The cooling coil is arranged in the descending channel; the reaction chamber wall is composed of a cylinder body side wall and a circular arc bottom; the reaction chamber wall body is connected to the housing through the upper supporter and the lower supporter; On the lower part of the sidewall of the reaction chamber wall or at the bottom of the arc circulating gas inlet port and catalyst discharge outlet exit; lower gas chamber raw material gas interface access, the lower chamber of the lower part of the liquid collection area , The bottom of the liquid collection zone outlet exit. In the invention, the cooling coil is used as the cooling device in the descending channel so that the raw material gas can be all synthesized into the target product through only one compression, thereby drastically reducing the power consumption and improving the catalytic efficiency.