This catalog, giving about 7000 galaxies behind the Milky Way between l = 210 degrees and 250 degrees, represents a systematic search for galaxies by means of 32 film copies of the UK Schmidt Southern Infrared Atlas on the Milky Way covering about 900 square degrees. In the search galaxies with apparent sizes greater than 0.1 mm on film (6.7 arcsec in size) were detected by visual inspection. The material and procedure of search are described as well as the detectability of galaxies in paper I and paper II appended before Vol. 1 and Vol. 2 of the catalog, respectively, which have been published in Publ. Astron. Soc. Japan, Vol. 42 (1990) and Vol. 43 (1991). The parameters of catalogued galaxies are also explained in paper I. Cross-identifications with other catalogs are shown in the last column. The search was performed by undergraduate students of a galactic astronomy program in Department of Astronomy, Kyoto University, in 1988 and 1989. Since the main researchers changed from the search in 1988 (Vol. 1) to that in 1989 (Vol. 2), a surface brightness level determining the extents of galaxy images somewhat differs between Vol. 1 and Vol. 2, yielding a difference of mean number densities of the detected galaxies between Vol. 1 and Vol. 2. The difference is examined in paper II. The detectability of galaxies, especially of smallest galaxies, increased in the overlap zones of adjacent fields of the Atlas; the effects are discussed in a paper (Yamada and Saito 1991, to appear in Publ. Astron. Soc. Japan, Vol. 43). In spite of such inhomogeneities in search for galaxies, the catalog is useful as a finding list of bright galaxies, peculiar galaxies, and nearby clusters of galaxies in the region behind the Milky Way. The machine-readable version of the catalog has been made through efforts of Mr. Shogo Nishida, Mr. Tadafumi Takata, and Professor Shiro Nishimura. This will be distributed upon request from Astronomical Data Analysis Center of the National Astronomical Observatory of Japan and other astronomical data centers. This work was supported by the Grant-in-Aid for General Scientific Research (01420002) of the Japanese Ministry of Education, Science, and Culture. June 1991 Mamoru Saito