We present UBVR photometry of eclipses in the post-common-envelope binary BE UMa. The eclipse is partial in all colours. We fit the eclipses to determine the orbital inclination and the radius of each star. For our best fit we find i = 82°4 ± 0°l, R1/a = 0.0781 ± 0.0001 and R2/a = 0.138 ± 0.001. Using the measured radial velocity of the secondary star, which we correct to account (approximately) for the asymmetric distribution of the line emission, we can calculate the system parameters of the binary for a given mass ratio. We find that for all mass ratios the primary star is a subdwarf and the secondary star lies well inside its Roche lobe. We use the fitted secondary star fluxes to determine its spectral type (G6V-K4V) and hence its mass, 0.69 <M2/M⊙ <0.89. This in turn limits the range of mass ratios possible to 0.64 < q <0.83. For these limits on q we find 0.83 < M1M⊙ <1.33 and 0.063 <R1/ R⊙ <0.077. Using model atmospheres we used the fitted primary star fluxes to determine the distance to the subdwarf. For a temperature of 90 000 <Te<125 000 K we find limits on the distance of 851 < D <1205 pc. The distance of the secondary star is consistent with the primary star's distance if the secondary star has spectral type K3-K4 and hence a distance of ˜ 1230-1071 pc.