  We investigate the potential of $e\gamma$ collisions to probe anomalous $Wtb$
couplings via the polarized single top quark production process $e^{+} \gamma
\to t \bar{b} \bar{\nu_{e}}$. We find 95% confidence level limits on the
anomalous coupling parameters $F_{2L}$ and $F_{2R}$ with an integrated
luminosity of $500 fb^{-1}$ and $\sqrt{s}=0.5, 1$ and 1.5 TeV energies. The
effects of top quark spin polarization on the anomalous $Wtb$ couplings are
discussed. It is shown that polarization leads to a considerable improvement in
the sensitivity limits.
