A hybrid optical waveguide circuit chip capable of predicting optical characteristics of a first optical waveguide circuit connected to optical elements where it is difficult to measure the optical characteristics. In the chip, a second optical waveguide circuit is disposed adjacent to the first optical waveguide circuit. One end face of the second optical waveguide circuit is terminated at one chip end face A of the chips, and at least one of the optical waveguide end faces at the other side of the second optical waveguide circuit is terminated at the other chip end face B of the chip, wherein the optical characteristics of the second optical waveguide circuit are measured, and the measured values are predicted as substantial optical characteristics of the first optical waveguide.