Bilingual child ability in two languages is become popular issue in the comparison of those two languages. In this paper, the Indonesian bilingual child has parent, school and course using English actively, then his environment using Bahasa Indonesia. This research was conducted to measure ability and difficulties faced by bilingual child in reading and writing in two languages Bahasa Indonesia- English. This journal applied a qualitative research design. Qualitative research is stated as naturalistic study that has the natural setting, as the direct source of data and the researcher is the key instrument  (Bogdan and Biklen, 1992). To specify the design in this journal, this qualitative method was used to analyze a specific person of Bilingual Child. The data were taken from observation, interview, video recording of the child’s reading the English and Bahasa Indonesia textbook story and written test of the child’s writing the English and Bahasa Indonesia summary of textbook story. In both English and Bahasa Indonesia, the reading difficulties appear related to pronunciation, intonation, expression and word stress and the writing difficulties appear related to relevance, organization, vocabulary and grammar.