New multi-color light curves of the very short period K-type eclipsing binary V1799 Ori were obtained and analyzed with the W-D code .
The photometric solutions reveal that the system is a W-type shallow-contact binary with a mass ratio of q = 1.335 ( \pm 0.005 ) and a degree of contact about f = 3.5 ( \pm 1.1 ) \% .
In general , the results are in good agreement with which is reported by Samec .
The remarkable O ’ Connell effects in the light curves are well explained by employing star spots on the binary surface , which confirms that the system is active at present .
Several new times of light minimum were obtained .
All the available times of light minimum were collected , along with the recalculated and new obtained .
Applying a least-squares method to the constructed O-C diagram , a new ephemeris was derived for V1799 Ori .
The orbital period is found to show a continuous weak increase at a rate of 1.8 ( \pm 0.6 ) \times 10 ^ { -8 } days \cdot yr ^ { -1 } .
The extreme-shallow contact , together with the period increase , suggests that the binary may be at a critical stage predicted by the TRO theory .