The invention discloses a signal processing system of a variable spectrum band multispectral camera based on an area array CCD. The signal processing system comprises a variable spectrum band timing sequence controller, a drive circuit, a frame transfer area array CCD with a charge pouring function, an analog-to-digital conversion circuit and a video processor. The variable spectrum band timing sequence controller generates a timing sequence signal used for driving the area array CCD to work according to a specified spectrum band; the drive circuit converts the timing sequence signal into a drive signal of a corresponding amplitude; the frame transfer area array CCD with the charge pouring function outputs spectrum band information under the action of the drive signal; the analog-to-digital conversion circuit converts an analog signal output by the CCD into a digital signal; and the video processor receives a digital image signal and processes image information according to input parameter requirements. Compared with the signal processing system of a traditional multi- linear-array multispectral camera, the signal processing system disclosed by the invention has the advantages of a large spectrum band number, real-time adjustable spectral range of the spectrum bands, and high spectrum band width adjustment precision, etc.