Many studies have shown that the imbalance representation between female and male is very pervasive in society especially in educational field. One of the issues raised is gender bias concepts found in both government and private publisher textbook. This research aims to investigate gender representation in Indonesian secondary English language textbook. Two different private English textbooks were chosen in order to see gender representation or male and female in the textbooks. The methodology used is a qualitative content analysis focusing on texts having pronoun she and/or he replacement. All data of the research were analyzed by using Halliday systemic functional linguistics including; theme system and transitivity (material, mental, relational, behavioral, and existential process). The findings show that male is out-number than female in both textbooks. In addition, the less existent of female is projected through the representation of female as a passive role. In terms of gender stereotyping, male is associated to his job and skill such as; wrestler, truck driver and king, whereas, female is associated to her marital status like; wife, widow, and daughter. Moreover, the choice of words is also considered sexism. It has been proven by the noun and adjective of female is collocated with feeling or sense, while male is collocated with talent, skill and appearance. All these findings may suggest that gender bias is depicted in both textbook. Finally, it is expected that the present research can be used as a reference in designing more gender friendly textbook and lesson for both textbook developer and teacher.