Metabotropic glutamate receptors (mGluRs) play important roles in neurotransmission, neuronal development, synaptic plasticity, and neurological disorders. Recent studies have revealed a sophisticated interplay between mGluRs and protein kinases: activation of mGluRs regulates the activity of a number of kinases, and direct phosphorylation of mGluRs affects receptor signaling, trafficking, and desensitization. Here we review the emerging literature on mGluR phosphorylation, signaling, and synaptic function.