  Pd$_{3}$Bi$_{2}$Se$_{2}$ has been proposed to be topologically non-trivial in
nature. However, evidence of its non-trivial behavior is still unexplored. We
report the growth and magneto-transport study of Pd$_{3}$Bi$_{2}$Se$_{2}$ thin
films, revealing for the first time the contribution of two-dimensional (2D)
topological surface states. We observe exceptional non-saturated linear
magnetoresistance which results from Dirac fermions inhabiting the lowest
Landau level in the quantum limit. The transverse magnetoresistance changes
from a semi-classical weak-field $B^{2}$ dependence to a high-field $B$
dependence at a critical field $B^{\star}$. It is found that $B^{\star} \propto
T^2$, which is expected from the Landau level splitting of a linear energy
dispersion. In addition, the magnetoconductivity shows signatures of 2D weak
anti-localization (WAL). These novel magnetotransport signatures evince the
presence of 2D Dirac fermions in Pd$_{3}$Bi$_{2}$Se$_{2}$ thin films.
