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This work reports new photometric results of eclipsing cataclysmic variableV617 Sagittarii (V617 Sgr). We analyzed the orbital period change of V617 Sgr,by employing three new CCD eclipse timings since 2010 along with all theavailable data from the literature. It was found that the orbital period ofV617 Sgr undergoes an obvious long-term increase, which confirms the resultrevealed by Steiner et al. (2006). The rate of orbital period increase wascalculated to be ${\dot{P}}$ = +2.14(0.05) $\times$ 10$^{-7}$ day/year. Thissuggests the lifetime of the secondary star will attain to the end in atimescale 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 of2.3 minutes may present in the O-C diagram. Dominated by the wind-accretionmechanism, high mass transfer from the low mass secondary to the white dwarf isexpected to sustain in the V Sge-type star V617 Sgr during its long-termevolution. The mass transfer rate $|\dot{M}_{tr}|$ was estimated to be in therange 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$_{\odot}$) whitedwarf primary will process stable nuclear burning, accrete a fraction of massfrom its companion to reach the standard Chandrasekhar mass limit ($\simeq$1.38 M$_{\odot}$), and ultimately produce a type Ia supernova (SN Ia) withinabout 4 $\sim$ 8 $\times$ 10$^{5}$ years or earlier.

The confirmation and revision on the orbital period change of the possible type Ia supernova progenitor V617 Sagittarii