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holecystokinin expressing interneurons (CCK INs) mediate behavior state dependent inhibition in cortical circuits and themselves receive strong GABAergic input. However it remains unclear to what extent GABABreceptors (GABABRs) contribute to their inhibitory control. Using immunoelectron microscopy we found that CCK INs in the rat hippocampus possessed high levels of dendritic GABABRs and KCTD12 auxiliary proteins whereas postsynaptic effector Kir3 channels were present at lower levels. Consistently whole cell recordings revealed slow GABABR mediated inhibitory postsynaptic currents (IPSCs) in most CCK INs. In spite of the higher surface density of GABABRs in CCK INs than in CA1 principal cells the amplitudes of IPSCs were comparable suggesting that the expression of Kir3 channels is the limiting factor for the GABABR currents in these INs. Morphological analysis showed that CCK INs were diverse comprising perisomatic targeting basket cells (BCs) as well as dendrite targeting (DT) interneurons including a previously undescribed DT type. GABABR mediated IPSCs in CCK INs were large in BCs but small in DT subtypes. In response to prolonged activation GABABR mediated currents displayed strong desensitization which was absent in KCTD12 deficient mice. This study highlights that GABABRs differentially control CCK IN subtypes and the kinetics and desensitization of GABABR mediated currents are modulated by KCTD12 proteins.