Abstract Aberrant epigenetic nuclear reprogramming of somatic nuclei is a major cause of low success in cloning. It has been demonstrated that treatment of histone deacetylase inhibitors (HDACi) enhances developmental potential of somatic cell nuclear transfer (SCNT) embryos by alteration of epigenetic status. The aim of the present study was to investigate the effect of oxamflatin, a novel HDACi, on the developmental competence of porcine SCNT embryos. Treatment with 1 μM oxamflatin for 9 h after activation of SCNT embryos increased both in vitro and in vivo developmental competence. Treatment of SCNT embryos with 1 μM oxamflatin significantly increased blastocyst rate and total cell number in blastocysts (33.3±6.0 and 73.1±1.6, respectively) than that of controls (10.3±3.7 and 54.1±3.5, respectively) or scriptaid (16.4±4.6 and 64.4±2.1, respectively). Moreover, oxamflatin showed significant higher overall cloning efficiency from 0.9% to 3.2%, whereas scriptaid demonstrated 0% to 1.8%. In conclusion, these results indicate that oxamflatin treatment improves the developmental competence of porcine SCNT embryos.