  We present a study of the high-resolution optical spectrum for the hot
post-asymptotic giant branch (post-AGB) star, Hen 3-1013, identified as the
optical counterpart of the infrared sourceIRAS 14331-6435. For the first time
the detailed identifications of the observed absorption and emission features
in the wavelength range 3700-9000 \AA\ is carried out. Absorption lines of HI,
HeI, CI, NI, OI, NeI, CII, NII, OII, SiII, SII, ArII, FeII, MnII, CrII, TiII,
CoII, NiII, SIII, FeIII and SIV were detected. From the absorption lines, we
derived heliocentric radial velocities of $V_r=-29.6\pm0.4$ km/s. We have
identified emission permitted lines of OI, NI, FeII, MgII, SiII and AlII. The
forbidden lines of [NI], [FeII], [CrII] and [NiII] have been identified also.
Analysis of [NiII] lines in the gaseous shell gives an estimate for the
electron density $N_e\sim10^7$ cm$^{-3}$ and the expansion velocity of the
nebula $V_{exp}=12$ km/s. The mean radial velocity as measured from emission
features of the envelope is $V_r=-36.0\pm0.4$ km/s. The Balmer lines H$\alpha$,
H$\beta$ and H$\gamma$ show P Cyg behaviour which indicate ongoing post-AGB
mass-loss. Based on ASAS and ASAS-SN data, we have detected rapid photometric
variability in Hen 3-1013 with an amplitude up to 0.2 mag in the V band. The
star's low-resolution spectrum underwent no significant changes from 1994 to
2012. Based on archival data, we have traced the photometric history of the
star over more than 100 years. No significant changes in the star brightness
have been found.
