  We present a study of three-dimensional structure of the Small Magellanic
Cloud (SMC). The $V$- and $I$-band light curves of the fundamental mode RR
Lyrae stars (RRab) obtained by the Optical Gravitational Lensing Experiment
(OGLE)-III project were utilized in order to comprehend the SMC structure. The
$[Fe/H]-P-\phi_{31}$ relation of \citet{jurc96} is exploited to obtain the
metallicities. From the three-dimensional RRab distance distributions,
northeast (NE) arm and main body of the galaxy is identified. Combining
metallicities with spatial distribution of these tracers, no radial metallicity
gradient in the SMC has been detected. Dividing the entire sample into three
parts: northeastern (NE), central and southwestern (SW), we find that the
central part has a significantly larger line of sight depth as compared to rest
of the parts, indicating that the SMC may have a bulge. Results obtained from
the $I$-band data seem to be reliable and were further substantiated using the
\citet{smol05} relation. Distribution of SMC RRab stars were modeled as a
tri-axial ellipsoid. Errors in structural parameters of the SMC ellipsoid were
obtained from Monte Carlo simulations. We estimated the axes ratios of the
galaxy as $1.00\pm 0.000:1.310\pm 0.029:8.269\pm0.934$, the inclination of the
longest axis with line of sight $i = 2^{\circ}.265\pm 0^{\circ}.784$, and the
position angle of the line of nodes $\theta_{\text{lon}}=74^{\circ}.307\pm
0^{\circ}.509$ from the variance weighted $I$-band determinations.
