Photometric solutions and the rate of mass transfer in U Sagittae Five-color intermediate-band photoelectric observations of the totallyeclipsing Algol binary U Sagittae were obtained from 1978 to 1985.Photometric solutions are made using WINK and the Wilson-Devineyprograms. The photometric mass ratio agrees well with the value foundrecently by Van Hamme and Wilson (1986). Small depressions in the lightcurves between phases 0.80 and 0.95 were produced by light extinction ina mass-transferring stream. A new method using the theory of streamstructure by Lubow and Shu (1975, 1976) is used to find M approximatelyequal to or less than 2x10 to the -7th solar mass per year. An attemptis made at a quantitative interpretation of small brightness changes ofthe cool star in this system.