  We present an analysis about the influence of an external magnetic field on
renormalons in a self interacting theory $\lambda \phi ^{4}$. In the weak
magnetic field region, using an appropriate expansion for the Schwinger
propagator's, we find new renormalons as poles on the real axis of the Borel
plane, whose position do not depend on the magnetic field, but where the
residues acquire in fact a magnetic dependence. In the strong magnetic limit,
working in the lowest Landau level approximation (LLLA), these new poles are
not longer present. We compare the magnetic scenario with previous results in
the literature concerning thermal effects on renormalons in this theory.
