A roof weather strip for use in a convertible car is composed of a plurality of weather strip pieces corresponding to the folding of a sliding roof thereof. When the sliding roof is unfolded to form a roof of the convertible car, longitudinal end parts of adjacent roof weather strip pieces contact each other to define a continuously extending roof weather strip for sealing a side edge of the sliding roof. Each of the weather strip pieces has a base portion, a tubular door glass-sealing portion, and a sliding roof-sealing portion. In each of the longitudinal end parts, the sliding roof-sealing portion is formed tubular, and the tubular sliding roof-sealing portion and the tubular door glass-sealing portion are closed with end faces, respectively, which are provided in each of the longitudinal end parts.