A cigarette injector for loading tobacco leaves into a hollow cigarette paper tube includes a housing having a tobacco cavity for the tobacco leaves disposing, an electric motor having an output shaft and a cigarette filling arrangement. The cigarette filling arrangement includes an elongated injection tube having a supplying end communicating with the tobacco cavity and a dispensing end for the cigarette paper tube encircling therewith, and an elongated tobacco feeder, which has a helicoid shape, having a driving end being driven to rotate via the output shaft of the electric motor and a feeding end extended within the injection tube through the tobacco cavity, wherein the tobacco feeder is driven to rotate for loading the tobacco leaves within the tobacco cavity into the cigarette paper tube through the injection tube.