A cDNA library was prepared from Vero cells infected with the Edmonston strain of measles virus. A number of viral specific cDNA clones were isolated and characterized by Northern blot hybridization analysis. A cDNA clone containing a 1500 base pair insert which hybridizes to a viral specific transcript of approximately 1500 nucleotides was subcloned into pSP64 and used as an in vitro transcription template. The resulting RNA transcript was translated in a cell-free system, giving rise to a polypeptide which comigrates on polyacrylamide gels with the authentic measles virus matrix protein and is immunoprecipitated with antisera specific for the matrix protein.