New Multi-color B V R _ { c } I _ { c } photometric observation are presented for W UMa type eclipsing binary V1073 Cyg .
The multi-color light curves analysis with the Wilson-Devinney ( W-D ) procedure acquired the absolute parameters of this system , showing that V1073Cyg is a shallow contact binary system with fill-out factor f = 0.124 ( \pm 0.011 ) .
We collected all available times of light minima spanning 119 years including CCD data to construct the O-C curve and made detailed O-C analysis .
The O-C diagram shows that the period change is complex .
There exist a long-term continuous decrease and a cyclic variation .
The period is decreasing at a rate of \dot { P } = -1.04 ( \pm 0.18 ) \times 10 ^ { -10 } days \cdot { cycle } ^ { -1 } , and with the period decrease , V1073 Cyg will evolve to deep contact stage .
The cyclic variation with a period of P _ { 3 } = 82.7 ( \pm 3.6 ) years and an amplitude of A = 0.028 ( \pm 0.002 ) day may be explained by the magnetic activity of one or both components or the light travel time effect ( LTTE ) caused by a distant third companion with M _ { 3 } ( { i ^ { \prime } } = 90 ^ { \circ } ) = 0.511 M _ { \odot } .