说明：  A method based on adap t ive filtering is p ropo sed to detect dim smallmoving target s in st rong undulant clut ter background. Thismethod ut ilizes the difference between target and clut ter w ith regard to stat ist ic charac2 terist ics, the consistency of moving target’s t rajecto ry, and the random fluctuat ion of no ise. A test based on in2 frared sequence images is p resented. The result s indicate that the method can supp ress the st rong undulant clut2 ter, and enhance target s efficient ly, and it can great ly imp rove the perfo rmance of detect ing dim small target s. Key words　St rong undulant clut ter background　D im small target　A dap t ive filter