We identified MIR181A1HG as a lncRNA that is ubiquitously expressed in non-mineralized tissues, highly expressed in proliferating MSCs and decreases in expression during osteogenesis. We demonstrate that knockdown of MIR181A1HG in hMSC-hTERT20 cells by CRISPRi during osteogenic differentiation causes an increase in alkaline phosphatase (ALP) activity and ALPL gene expression. Increased expression of several extracellular matrix proteins was noted. We identified MIR181A1HG as a nuclear lncRNA that binds to chromatin and where it regulates gene expression, including the transcription factor SOX5. These results reveal that MIR181AHG may act as a negative regulator of osteoblast differentiation, thereby providing a novel mechanism of regulatory control of osteogenesis. Overall design: Expression of the lncRNA MIR181AHG was knocked down by CRISPRi using pLV hU6-sgRNA hUbC-dCas9-KRAB-T2a-GFP in TERT immortalized human mesenchymal stromal cells (hMSC-hTERT20). Transcriptome changes were examined during osteogenic differentiation at three time points (Day 0, 7 and 14) after lncRNA interference.