In continuation of studies on highly hydroxylated steroidal starfish metabolites, a novel polyhydroxysteroidal glycoside, leptasteroside L ((24R)-29-O-(β-D-glucopyranosyl)-24-ethyl-5α-cholestane-3β,5,6β,8,15α,29-hexaol), was isolated from the starfish Leptasterias polaris acervata. Its structure was established mainly by 1H and 13C NMR spectroscopy, acid hydrolysis (identifying D-glucose), comparison with model compounds, and nuclear Overhauser effect (NOE) experiments, confirming a (24R)-24-ethylcholestane side chain with a β-D-glucopyranosyl residue at C(29)—a rare feature for starfish steroidal glycosides. Additionally, deoxyguanosine, thymidine, deoxyadenosine, tryptophan, and tyramine were isolated from the methanolic extract and identified via NMR and mass spectrometry.