A new type of double function optical circulator for double fibers is proposed in this paper. Two fiber tips and lens twice are employed in this kind of device. Because two fiber tips and lens twice are used, the function of optical circulator is duplicated in comparison with conventional optical circulator with single fiber tip. Thus the optical circulator has a low cost and a small volume comparatively. Typical insertion loss and isolation of the developed circulator are analyzed and discussed by using Jones-Matrix in theory. The analysis results show that the above two characteristics are as good as conventional optical circulator′s characteristics. The isolation is increasing with increment of extinction ratio. The surface reflectivity and material absorption are the main source of the insertion loss. The rotator errors of the rotators have an important effect on the isolation. The higher the errors, the lower the isolation. It′s very important for using optical material with high transmission and high extinction ratio to achieve low insertion loss and high isolation. Also the rotation error of the rotators must be reduced in assembly to win low insertion loss and high isolation. Details of design and high characteristics of this circulator are presented.