The distinction between type I and type II superconductivity is re-examined in the context of the SO(5) model recently put forth by Zhang. Whereas in conventional superconductivity only one parameter (the Ginzburg-Landau parameter $kappa$) characterizes the model, in the SO(5) model there are two essential parameters. These can be chosen to be $kappa$ and another parameter, $beta$, related to the doping. There is a more complicated relation between $kappa$ and the behavior of a superconductor in a magnetic field. In particular, one can find type I superconductivity, even when $kappa$ is large, for appropriate values of $beta$.
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