A detailed analysis by means of the Wilson and Devinney method of the UBV photometry of BR Muscae is shown. Different values are investigated of the mass-ratio q between 0.4 and 1.5. Finally, it is established that the best solutions correspond to values of q close to unity. A degree of contact of about 11% is found. According to the period-spectral type relation, BR Muscae appears to be little evolved. Its relation with the remaining massive contact binaries is shortly discussed.