Later, to meet the need of the growing industry, the second naphtha cracker was completed in 1975. It produces ethylene, propylene and butadiene as raw materials.
其後，為增加供應烯烴原料，復於六十四年在高雄煉油總廠完成第二輕油裂解工場，年產乙烯二十三萬公噸及丙烯、丁二烯等，以供應石油化學下游工業原料的需要，並已於當年十月正式試車生產。