A new indolizinium alkaloid, named as cyclizidine J (1), was identified from Gause's liquid fermentation of marine-derivedStreptomycessp. HNA39. Its structure was elucidated by extensive NMR spectroscopic methods, HRESIMS data, and ECD calculations. To our best knowledge, compound1was a unique cyclizidine-type alkaloid that contain a chlorine atom substituted at position C-8. Unfortunately, biological evaluation of1exhibited no active against PC-3 cancer cell line, BRD4, and ROCK2 protein kinase.