Fiber-optic passive devices are so suitable for current situation that they have greatly been grown with rapid developments and broad applications of optical fiber technology, within which optical fiber fused tapering devices are more noticeable due to their simple manufacture, stable performance, cheaper price and super specification. Among the above ones, optical fiber couples are widely used as fundamental devices. Recently, super-flat-wideband single-mode optical fiber couplers become a popular research area with urgent development of all-fiber communications. Super-flat-wideband single-mode optical fiber couplers have been developed by the architectural method of special phase compensation, whose operating wavelength band is from 1250 nm to 1650 nm, 3 dB-insertion-loss maximum deviation within the band is less than 0.4 dB, maximum excess loss within the band is less than 0.1 dB, directionality is greater than 66.5 dB, and polarized dependent loss is less than 0.1 dB. In the light of the method high rate of the finished products, meanwhile, a batch productions are feasible.