  We present the results of the study of the close binary UU Cassiopeiae based
on previously published multi wavelength photometric and spectroscopic data.
Based on eclipse timings of the last 117 years, we find an improved orbital
period of $\rm P_{o} = 8.519296(8)$ d. In addition, we find a long cycle of
length $T$ $\sim$ 270 d in the $I_c$-band data. There is no evidence for
orbital period change during the last century, suggesting that the rate of mass
loss from the system or mass exchange between the stars should be small.
Sporadic and rapid brightness drops of up to $\Delta$$V$ = 0.3 mag are detected
during the whole orbital cycle and infrared photometry clearly suggests the
presence of circumstellar matter. We model the orbital light curve of 11
published datasets fixing the mass ratio and cool star temperature from
previous spectroscopic work; $q$= 0.52 and $T_c$= 22 700 K. We find a system
seen at angle 74 degrees with a stellar separation of 52 ${\rm R_{\odot}}$, a
temperature for the hotter star $T_h$= 30 200 $K$ and stellar masses 17.4 and 9
${\rm M_{\odot}}$ , radii 7.0 and 16.9 ${\rm R_{\odot}}$ and surface gravities
log g = 3.98 and 2.94, for the hotter and cooler star, respectively. We find an
accretion disk surrounding the more massive star, with a radius of 21 ${\rm
R_{\odot}}$ and vertical thickness in its outer edge of 6.5 ${\rm R_{\odot}}$,
mostly occulting the hotter star. Two active regions hotter than the
surrounding disk are found, one located roughly in the expected position where
the stream impacts the disk and the other one in the opposite side of the disk.
Changes are observed in parameters of the disk and spots in different datasets.
