  We present the first detailed X-ray study and simultaneous optical
observations of the active fast rotating star FR Cnc. The X-ray spectra are
found to be explained by two-temperature plasma model with temperature of cool
and hot components of 0.34 and 1.1 keV, respectively. The X-ray light curve in
the 0.5 -- 2.0 keV energy band is found to be rotationally modulated with the
degree of rotational modulation of ~17%. We have also found that the X-ray
light curve is anti-correlated with the optical light and colour curves in the
sense that maximum X-ray light corresponds to minimum optical light and cooler
region on the surface of FR Cnc. The X-ray luminosity of FR Cnc is found to be
almost consistent in the last 30 years with an average value of 4.85x10^{29}
erg/s in the 0.5 -- 2.0 keV energy band.
