The utility model relates to a nuclei of condensation particle growing device, including saturated cabin and refrigeration cabin, the refrigeration cabin is the cabin in refrigeration outer cabin and the refrigeration of sealing connection in refrigeration outer cabin, and the under -deck sets up the gas passage in the refrigeration, the inside cavity in saturation cabin, saturated cabin one end with outer cabin fixed connection refrigerates, but other end plug be provided with the alcohol core, the alcohol in -core is provided with the gas passage, compress tightly the semiconductor refrigeration block who has the central through hole in saturation cabin and the refrigeration between the cabin, the interior cabin of refrigeration is hugged closely through first conducting strip to semiconductor refrigeration block's cold junction, and saturated cabin is hugged closely through the second conducting strip in semiconductor refrigeration block's hot junction, gas passage in the alcohol core passes through the gas passage intercommunication in semiconductor refrigeration block and the interior cabin of refrigeration.