We report results of a BeppoSAX ( 0.1–200 keV ) observation of the Z-type low mass X-ray binary GX 17+2 .
The source was on the so-called Horizontal and Normal branches .
Energy spectra were selected based on the source position in the X-ray hardness-intensity diagram .
The continuum could be fairly well described by the sum of a \sim 0.6 keV blackbody , contributing \sim 10 \% of the observed 0.1 - 200 keV flux , and a Comptonized component , resulting from upscattering of \sim 1 keV seed photons by an electron cloud with temperature of \sim 3 keV and optical depth of \sim 10 .
Iron K-line and edge were also present at energies \sim 6.7 and \sim 8.5 keV , respectively .
In the spectra of the Horizontal branch a hard tail was clearly detected at energies above \sim 30 keV .
It could be fit by a power law of photon index \sim 2.7 , contributing \sim 8 \% of the source flux .
This component gradually faded as the source moved towards the Normal branch , where it was no longer detectable .
We discuss the possible origin of this component and the similarities with the spectra of Atoll sources and black hole X-ray binaries .