A pharmaceutical composition for the treatment and/or prevention of cerebral ischemic diseases, which comprises two components, i.e. an astrocyte function-improving agent, preferably a compound represented by the formula (I): (wherein R.sup.6 is hydroxy, etc., (1) n is 1, R.sup.11 is hydrogen and R.sup.5 is (alkyl of which one carbon atom is substituted by fluorine)-CH.sub.2-- or (2) n is 0 or 1, R.sup.11 is hydrogen, etc., and R.sup.5 is alkyl, etc.) and a thrombolytic agent, preferably tissue plasminogen activator, as active ingredients. The pharmaceutical composition of the present invention exhibits a synergistic therapeutic effect compared to independent administration of an astrocyte function-improving agent and a thrombolytic agent.