Lamellarin N (Lam N) is a member of an interesting marine natural product class isolated from mollusks and subsequently found in ascidians and sponges. The limited aqueous solubility of Lam N hinders further studies on its cytotoxic activity against cancer cells. In this study, micelles comprising poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-b-PCL) and poly(ethylene glycol)-block-poly(D, L-lactide) (PEG-b-PLA) were developed to circumvent Lam N limited aqueous solubility. The results showed that an increase in the molecular weight of both core materials resulted in higher Lam N loading content, whereas the release of Lam N decreased as a function of molecular weight of PCL and PLA. With less hydrophobic property, PLA micelles provided faster Lam N release. Thus, polymeric micelles could be utilized as controlled-release delivery systems for poorly water soluble Lam N.