A dispersion compensation device comprises a chirped grating, and a first optical unit for guiding at least a lightwave signal with a wavelength of &lgr;i that needs a positive dispersion compensation and is applied thereto to one end portion of the chirped grating whose grating pitch is shorter, and for furnishing light reflected by the chirped grating to outside the device. The device further comprises a second optical unit for guiding at least a lightwave signal with a wavelength of &lgr;i that needs a negative dispersion compensation and is applied thereto to another end portion of the chirped grating whose grating pitch is longer, and for furnishing light reflected by the chirped grating to outside the device. Both the first and second optical units can be either optical circulators or optical couplers.