This study investigates the inclusion of health education concepts in biology textbooks in the United States of America and Singapore. It employs a content analysis methodology to examine biology textbooks, considering the theme as a unit and dividing health concepts into four main fields. The findings for both countries indicate that the field of "diseases and epidemics" occurred most frequently, followed by "disease prevention and treatment," then "environment." Finally, "food and nutrition" occurred least frequently. The overall scores for the textbooks of these two countries, with regard to the inclusion of health concepts, reveal a significant difference in favour of the USA. Based on these findings, the researcher recommends that school textbooks should increase their coverage of health concepts, especially in the fields of the "environment" and "food and nutrition," in order to provide students with more accurate, reliable health information and experiences that are consistent with current needs.