The present invention relates to a method for continuous production of carbon nanotubes in a nano-agglomerate fluidized bed, which comprises the following steps: loading transition metal compounds on a support, obtaining supported nanosized metal catalysts by reducing or dissociating, catalytically decomposing a carbon-source gas, and growing carbon nanotubes on the catalyst support by chemical vapor deposition of carbon atoms. The carbon nanotubes are 4˜100 nm in diameter and 0.5˜1000 μm in length. The carbon nanotube agglomerates, ranged between 1˜1000 μm, are smoothly fluidized under 0.005 to 2 m/s superficial gas velocity and 20-800 kg/m3 bed density in the fluidized-bed reactor. The apparatus is simple and easy to operate, has a high reaction rate, and it can be used to produce carbon nanotubes with high degree of crystallization, high purity, and high yield.