A chemical investigation of the liver oil from the shark Squalusjaponicus Ishikawa, collected in Quy Nhon Bay led to the isolation of four compounds. Their structures were determined to be ethyl (5Z, 8Z, 11Z, 14Z, 17Z) eicosapentanoate (1), glycerol 1,3-dioleate, 2-palmitate (2), 1-O-(9Z-octadecenyl) 2-O-hexadecanoyl 3-O-(9Z-octadecenoyl) glycerol (3) and selachyl alcohol (4) by mean spectroscopic methods including ESI-MS, 10- and 2D-NMR.