The fourth annual catalog of the Tokyo PMC is presented for 3800 stars (Part I and Part II) which had been observed at least two times in the 1988 period, that is, from January 1, 1988, to December 31, 1988. The positions of the stars given in the catalog are those at the mean epoch of observations. The coordinates of the catalog are based on the FK5 system, and are referred to the equinox and equator of J2000.0. The positions of five major and nine minor planets are also given in the present catalog (Part III) for all individual observations made in 1986 to 1988. The planetary positions are based on the same coordinate systems as those of the corresponding annual star catalogs, the Tokyo PMC Catalogs 86, 87, and 88. The mean trends of the observed positions - FK5 positions for the basic FK5 stars are constructed and compared with those of the Tokyo PMC Catalogs 86 and 87. As for the planets, their observed positions are compared with the positions of the JPL's planetary ephemeris DE200. We find that the ephemerides of the outermost planets, Uranus and Neptune, have some systematic deviations of a few tenths of arcsec in longitudes.