By coupling nitric oxide (NO)-donor moieties with a natural antihypertensive product (±)-7,8-dihydroxy-3-methyl-isochroman-4-one [(±)-XJP] and its analogue (±)-XJP-B, a series of novel NO-releasing isochroman-4-one derivatives were designed and synthesized. The NO-releasing assay indicated that compounds Ia, Id, IIIb and IIIe released the maximum amount of NO. The maximum reductions of blood pressure of Ia, IIIb and IIIe in SHRs were nearly 40%, which was obviously superior to that of the lead compounds and comparable to that of reference drug captopril. These results suggested that NO-donor/natural product hybrids may provide a promising approach for the discovery of novel antihypertensive agents.