  We present an analysis of UBVR$_{\rm C}$I$_{\rm C}$JH photometry and
phase-resolved optical spectroscopy of NSVS 14256825, an HW Vir type binary.
The members of this class consist of a hot subdwarf and a main-sequence
low-mass star in a close orbit ($P_{\rm orb} ~ 0.1$ d). Using the
primary-eclipse timings, we refine the ephemeris for the system, which has an
orbital period of 0.11037 d. From the spectroscopic data analysis, we derive
the effective temperature, $T_1 = 40000 \pm 500$ K, the surface gravity, $\log
g_1 = 5.50\pm0.05$, and the helium abundance, $n(\rm He)/n(\rm
H)=0.003\pm0.001$, for the hot component. Simultaneously modelling the
photometric and spectroscopic data using the Wilson-Devinney code, we obtain
the geometrical and physical parameters of NSVS 14256825. Using the fitted
orbital inclination and mass ratio ($i = 82\fdg5\pm0\fdg3$ and $q = M_2/M_1 =
0.260\pm0.012$, respectively), the components of the system have $M_1 = 0.419
\pm 0.070 M_{\odot}$, $R_1 = 0.188 \pm 0.010 R_{\odot}$, $M_2 = 0.109 \pm 0.023
M_{\odot}$, and $R_2 = 0.162 \pm 0.008 R_{\odot}$. From its spectral
characteristics, the hot star is classified as an sdOB star.
