A photometric analysis of the very-short-period (∼o d.43) dwarf binary with a classical Algol-type curve, Viooi Cassiopeiae, is presented. Its short period, similar to the majority of W UMa variables, yet distinct EA light-curve, make it a rare and interesting system for photometric investigation. The photometric VRI standard magnitudes suggest a K 4 spectral type. A period study and synthetic BVR and I light-curve solutions are presented. The I curve was modelled separately, but there are only slight differences in the solutions. Our present solution, following a mass-ratio search, gives a mass ratio of near 038, a temperature difference of ∼8oo K, with fill-out factors of∼70% and ∼85% of the primary and secondary star contact Roche lobes, respectively. A cool spot with ∼40° radius was used to fit the interesting asymmetries of the light-curve. The secondary component is in the MI-M 5 range of main-sequence spectral types.
