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We report liquid-phase exfoliation (LPE) of bulk layered-structure semiconductor, MnIn 2 Se 4 , to nanoscale thick sheets by ultrasonication followed by sequential centrifugation at 2000, 5000, and 7500 rpm. The nanosheets exfoliated by LPE in isopropyl alcohol show an average thickness of 50, 40, and 14 nm, respectively. The smallest of these values corresponds approximately to ten 7-atom thick [Se–In–Se–Mn–Se–In–Se] layers that compose the bulk structure of MnIn 2 Se 4 . Both the bulk material and the exfoliated samples show photoluminescence, but the weak shoulder observed from the indirect band gap emission is obviously suppressed in the nanosheet samples as compared to the bulk sample. Similar to the bulk, the nanosheets isolated at 2000 and 5000 rpm exhibit spin-glass behavior with a freezing temperature of ∼3 K. In contrast, the nanosheets isolated at 7500 rpm do not exhibit any anomalies in their low-temperature magnetic behavior. These results demonstrate the possibility to extend the LPE technique to van-der-Waals materials with several-atom-thick layers.