  The contact eclipsing binary system XX Leonis (P = 0.97 days, sp A8) has been
analysed using the PHOEBE programme, based on the Wilson Devinney code. The
BVRI light curves were obtained during spring 2006 using the 20-cm telescope
and ST-7 CCD detector. The effective temperature of the primary component
determined from the photometric analysis is T=(7889+/-61)K, the inclination of
the orbit is i=(89.98+/-2.45)deg and the photometric mass ratio
q=(0.41+/-0.01). Also the third body hypothesis was suggested, based on the
period analysis using 57 minimum times and resulting the period of the third
body p3= (52.96+/-0.01)yr, amplitude A=(0.057+/-0.029)d and eccentricity
e=(0.79+/-0.08) which gives the minimum mass m3,min=(3.6+/-0.8)M_sun.
