The invention discloses a burner for ignition and low-load stable combustion of a fluidized bed boiler, and the burner belongs to fluidized bed boiler ignition and low-load stable combustion technologies. The novel burner has the micro-oil ignition or less-oil ignition and low-load stable combustion functions, and mainly aims to achieve cold-state ignition and low-load stable combustion for the fluidized bed boiler. The burner comprises an oil combustor, an oil gun ignition device, a secondary oil combustor, a fire check device, a swirl flow air channel, swirl vanes, a burner convergent section, a burner divergent section, a cooling air channel and a uniform-temperature mixing section. As for design, the ignition device is used for atomizing fuel through high-pressure air firstly, a small amount of fuel is burnt sufficiently in the oil combustor, an oil gun adopts mechanical atomization or air atomization, then the fuel is completely burnt out in the secondary combustor through primary air, and flames are pushed to spray out of the secondary combustor; the swirl vanes enable the primary air in the swirl flow air channel to rotate and be fully mixed with the flames spraying out of the secondary combustor, and the effect of cooling the secondary combustor is realized; and finally, air temperatures are uniformly mixed at the uniform-temperature section.