The purpose of this study was to analyse fusing science and STEAM factors of learning contents related to life science presented in high school science textbooks, and then to examine the connection between ``Science`` and ``Life Science I`` or ``Life Science II``. ``Science`` textbooks were published by 7 publishers, which were developed according to 2009 Science Curriculum. ``Life Science I`` and ``Life Science II`` textbooks were published by 5 publishers. Learning contents were analysed to identified by fusing science factors(biology, chemistry, physics and earth science) and STEAM factors (science, technology, engineering, art and mathematics). There was lower proportion of fused science subjects, and more than 50% of learning topics were related to only one science subject. The integrative proportion of STEAM factors of learning topics wasn`t higher, too. Most learning topics of ``Science`` had no relationship with ``Life Science I`` or ``Life Science II``. The results suggested that learning programs should be developed to complement with the lack of fusing science factors and STEAM ones for high school students, and learning contents or topics of ``Science`` be harmonized in aspects of connection between subjects concerned with.