The invention relates to a modularized heat-capacity type thrust chamber comprising an injector assembly, a head top cap, a head bottom cap, a body cylinder section and a tail spray pipe, wherein the injector assembly, the head top cap and the head bottom cap are connected by adopting bolts to form the head of the thrust chamber; the body cylinder section is in a sectional type structure; and each section of the cylinder section, the tail spray pipe and the head of the thrust chamber are connected by adopting bolts. The head and the body of the thrust chamber, and the cylinder section and the spray pipe section are sealed in the mode of compacting expanded graphite sealing rings between a boss and a groove. The head can be made of a stainless steel material, the body cylinder section is made of red copper, and the spray pipe section is made of a high temperature-resistant material. By adopting the invention, when performing the experimental study on a rocket engine, experimenters can conveniently replace the module of the engine to change the studied parameter for carrying out comparative analysis, therefore, the cost is obviously reduced.