Optical transmission apparatus, optical transmission system and dispersion compensating method

In a long-distance and large-capacity optical transmission system, a dispersion compensating device showing a wavelength-dependency of dispersion characteristic is provided in a transmission line which makes a connection between a transmission terminal node and a reception terminal node. The reception terminal node acquires a dispersion quantity relative to single-wavelength light outputted from a wavelength-variable transmitter which is provided in the transmission terminal node for outputting single-wavelength light, and transmits wavelength control information corresponding to the acquired dispersion quantity to the transmission terminal node. The transmission terminal node varies the wavelength of the transmitter on the basis of the transmitted wavelength control information. This enables acquiring an optimum dispersion compensation quantity with a simple configuration and optimizing a dispersion compensation quantity for each channel at the transmission of wavelength-multiplexed light.