  We have studied the effect of spin-orbital coupling (SOC) on electronic
transport properties of the thermoelectric material
$\beta$-K$_{2}$Bi$_{8}$Se$_{13}$ via magnetoresistance (MR) measurements. We
found that the strong SOC in this material results in weak antilocalization
(WAL) effect, which can be well described by the three-dimensional weak
localization model. The phase coherence length extracted from theoretical
fitting exhibits a power-law temperature dependence with an exponent around
2.1, indicating that the electron phase dephasing is governed by electron -
transverse phonon interactions. Like in topological insulators, the WAL effect
in $\beta$-K$_{2}$Bi$_{8}$Se$_{13}$ can be quenched by magnetic impurities (Mn)
but is robust against non-magnetic impurities (Te). Although our
magnetotransport studies do not provide any evidences for topological surface
states, our analyses suggest that SOC plays an important role in determining
thermoelectric properties of $\beta$-K$_{2}$Bi$_{8}$Se$_{13}$.
