Abstract: Many cytokininbinding proteins(CBPs) have been characterized in plants. They may be involved in the cytokinin signal transduction, cytokinin transport and cytokinin metabolism. Evidences show that most of the cytokinin receptors are associated with membranes, mediating the cytokinin signal trabsduction across the membrane via G Protein coupled signaling pathway or a two_component signaling pathway. A few cytokinin receptors may be in the cytosol, regulating the nuclear gene expression directly when combined with cytokinin. This article reviews the studies on CBPs. The putative types of cytokinin receptors and the mechanisms of the CBPs actions are also discussed.