  In this paper we are concerned with the SIR (Susceptible-Infective-Removed)
epidemic on open clusters of bond percolation on the squared lattice. For the
SIR model, a susceptible vertex is infected at rate proportional to the number
of infective neighbors while an infective vertex becomes removed at a constant
rate. A removed vertex will never be infected again. We assume that there is
only one infective vertex at $t=0$ and define the critical value of the model
as the maximum of the infection rates with which infective vertices die out
with probability one, then we show that the critical value is
$\big(1+o(1)\big)/(2dp)$ as $d\rightarrow+\infty$, where $d$ is the dimension
of the lattice and $p$ is the probability that a given edge is open. Our result
is a counterpart of the main theorem in \cite{Hol1981} for the contact process.
