The invention discloses a low-emission combustion chamber with a double-layer axial hydrocyclone at a precombustion stage. The combustion chamber is of a single annular cavity structure and structurally comprises a pressure expander, a combustion chamber exterior casing, a combustion chamber interior casing, a flame tube and a combustion chamber head; all combustion-used air enters the flame tube through the combustion chamber head, a staged combustion scheme is adopted, and the combustion is divided into into the precombustion stage and a primary combustion stage; a premixed combustion mode is adopted at the primary combustion stage, and a diffusive combustion mode serves as the main mode of the precombustion stage; the double-layer axial hydrocyclone is adopted at the precombustion stage, two blasts of rotational flow can maintain individual flowing through a partition plate, and momentum loss due to the fact that the two blasts of rotational flow make contact with each other too early is avoided; the two blasts of rotational flow are utilized for reinforcing fuel oil atomization and mixing, meanwhile, reasonable recirculating zone distribution is generated, efficient and stable combustion under small working conditions is guaranteed, and meanwhile pollutant emission is lowered; the combustion chamber is simple in structure at the precombustion stage and easy to machine and install, combustion chamber emission under small working conditions can be lowered, and thereby the low emission performance of a total landing and taking-off cycle of the combustion chamber is improved.