AbstractThe existence of ether‐linked phospholipids, including 1‐O‐alk‐1′‐enyl‐2‐acyl and 1‐O‐alkyl‐2‐acyl‐sn‐glycero‐3‐phosphocholines and ethanolamines in bonitoEuthynnus pelamis (Linnaeus) white muscle, was investigated by gas chromatography and gas chromatography‐mass spectrometry. Chemical ionization (iso‐butane) mass spectrometry of trimethylsilyl ethers derived from the corresponding ether‐linked glycerophospholipids proved effective not only for determining molecular weights but also for structural identification based on the ions [M−R]+, [M−RO]+ and [M+1]+. 1‐O‐Alk‐1′‐enyl‐2‐acyl‐sn‐glycero‐3‐phosphocholine and ethanolamine accounted for 3.0–6.0% and 3.6–7.6% of the total glycerophospholipids, respectively. 1‐O‐Alkyl‐2‐acyl‐sn‐glycero‐3‐phosphocholine and ethanolamine were also determined for one fish and accounted for 1.4% and 0.6% of the total glycerophospholipids, respectively. The predominant long chains in thesn‐1 position of the glycerol moieties were 16∶0, 18∶0 and 18∶1 in the case of the alkenylacyl and alkylacyl components. Fatty acid distribution of individual glycerophospholipids was also determined.