Let $\Sigma(K; p/q)$ be the result of $p/q$-surgery along
a knot $K$ in a homology 3-sphere $\Sigma$. We investigate
the Reidemeister torsion of $\Sigma(K; p/q)$. Firstly, when
the Alexander polynomial of $K$ is the same as that of a torus
knot, we give a necessary and sufficient condition for the
Reidemeister torsion of $\Sigma(K; p/q)$ to be that of a lens
space. Secondly, when the Alexander polynomial of $K$ is
of degree $2$, we show that if the Reidemeister torsion of
$\Sigma(K; p/q)$ is the same as that of a lens space, then
$\varDelta_K(t)=t^2-t+1$.