In the past decade, drug delivery systems that can respond to the tumor microenvironment or external stimuli have emerged as promising platforms for treating malignancies due to their improved antitumor efficacy and reduced side effects. In particular, biodegradable polymeric micelles have attracted increasing attention and been rapidly developed as a distinct therapeutic to overcome limitations of conventional chemotherapeutic anticancer drugs. Because of their advantages with respect to biocompatibility, degradability, circulation time, and tumor accumulation, considerable effort has been dedicated to the developing and optimizing micellar systems during the past few years. This review highlights recent advances concerning stimuli-responsive micelles made of biodegradable polypeptide and polyester as nanocarries for drug delivery, and especially limits the content to pH sensitive, redox sensitive, and photo-sensitive micellar systems for safe and efficient cancer chemotherapy.