According to the latitude of the astrolabe ), a zone comprised between and in declination can be observed at zenith distance from Santiago. A zone around the southern celestial pole of about wide in declination is not observable since in this zone the small declination circles of the stars do not intercept the almucantar. The observational program at zenith distance consists of eleven groups of 28 stars each one. The star distribution in azimuth in each group is as uniform as possible. The eleven groups comprise 166 FK5 and 103 FK5 Extension stars. Of these 269 stars, 39 are observed in double transit. The observations were reduced following the IAU76/82 resolutions on fundamental constant and apparent places computation (Kaplan 1981; Chollet 1984). At zenith distance the stars images as observed with the astrolabe, show permanently a rather strong agitation due to atmospheric effects. The effect of the image agitation on the results is clearly reflected in the precision of the mean zenith distance residuals of the stars. They were obtained with an average mean error of , which is more or less twice the average mean error obtained at Santiago from observations at zenith distance (Noël & Débarbat 1990).