Abstract: Harbor detection is an important aspect for remote sensing ocean application research. Fast and accurate harbor detection can greatly improve the ability of automatic interpretation for remote sensing image shipside buildings and ships inside ports. By having a detailed research on harbor object disposal， this paper established harbor model and advance knowledge， and proposed a harbor detection method of remote sensing images based on model. Besides， aiming at the shortage that proposed method has a little far in locating harbor range， this paper defined the principal axis of harbor object and calculated harbor circumrectangle which has a higher location precision. Compared with an existing harbor detection algorithm， our experiments show that novel method has a whole harbor detection， exact location and better universal.