  This work reports new photometric results of eclipsing cataclysmic variable
V617 Sagittarii (V617 Sgr). We analyzed the orbital period change of V617 Sgr,
by employing three new CCD eclipse timings since 2010 along with all the
available data from the literature. It was found that the orbital period of
V617 Sgr undergoes an obvious long-term increase, which confirms the result
revealed by Steiner et al. (2006). The rate of orbital period increase was
calculated to be ${\dot{P}}$ = +2.14(0.05) $\times$ 10$^{-7}$ day/year. This
suggests the lifetime of the secondary star will attain to the end in a
timescale of 0.97 $\times$ 10$^6$ years faster than that predicted previously.
In particular, a cyclic variation with a period of 4.5 year and an amplitude of
2.3 minutes may present in the O-C diagram. Dominated by the wind-accretion
mechanism, high mass transfer from the low mass secondary to the white dwarf is
expected to sustain in the V Sge-type star V617 Sgr during its long-term
evolution. The mass transfer rate $|\dot{M}_{tr}|$ was estimated to be in the
range of about 2.2 $\times$ 10$^{-7}$ to 5.2 $\times$ 10$^{-7}$ M$_{\odot}$
yr$^{-1}$. Accordingly, the already massive ($\geq$ 1.2 M$_{\odot}$) white
dwarf primary will process stable nuclear burning, accrete a fraction of mass
from its companion to reach the standard Chandrasekhar mass limit ($\simeq$
1.38 M$_{\odot}$), and ultimately produce a type Ia supernova (SN Ia) within
about 4 $\sim$ 8 $\times$ 10$^{5}$ years or earlier.
