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EX Dra is a long-period eclipsing dwarf nova with $\sim2-3$ mag amplitudeoutbursts. This star has been monitored photometrically from November, 2009 toMarch, 2016 and 29 new mid-eclipse times were obtained. By using new datatogether with the published data, the best fit to the $O-C$ curve indicate thatthe orbital period of EX Dra have an upward parabolic change while undergoingdouble-cyclic variations with the periods of 21.4 and 3.99 years, respectively.The upward parabolic change reveals a long-term increase at a rate of$\dot{P}={+7.46}\times10^{-11}{s} {s^{-1}}$. The evolutionary theory ofcataclysmic variables (CVs) predicts that, as a CV evolves, the orbital periodshould be decreasing rather than increasing. Secular increase can be explainedas the mass transfer between the secondary and primary or may be just anobserved part of a longer cyclic change. Most plausible explanation for thedouble-cyclic variations is a pair of light travel-time effect via the presenceof two companions. Their masses are determined to be$M_{A}sini'_{A}=29.3(\pm0.6) M_{Jup}$ and $M_{B}sini'_{B}=50.8(\pm0.2)M_{Jup}$. When the two companions are coplanar to the orbital plane of thecentral eclipsing pair, their masses would match to brown dwarfs.

Double cyclic variations in orbital period of the eclipsing cataclysmic variable EX Dra