The present invention relates to a continuous reactor a method for manufacturing nanoparticles. The reactor of the present invention includes: a plurality of first inputs for individually inputting a plurality of reagents; a first mixing part connected to the first inputs to mix the reagents; N number of first reaction units, each comprising a plurality of first diverging channels and a first converging channel to form a channel having the first diverging channels and the first converging channels alternately connected to one another in series for N times of diverging-converging actions, wherein N.gtoreq.1, and the first diverging channels of a 1.sup.st one of the first reaction units are connected to the first mixing part; and a first output connected to the first converging channel of an N.sup.th one of the first reaction units, so as to output a product of nanoparticles. |