This research is aimed to determine biology modules guided inquiry subtance ecosystem for class X MA. This was a Research and Development (R & D). The population is entire students class X SMA N 1 Tambusai. Sampels in this study amouned to 30 students. Data collecting techniques by using a question naire as for the acquisition of all validation in clude validation percentages material acquisition 77.91% category of “decent”. The media of the percentage of 88.12% category of “very decent”, linguists validation percentage 81.25% category of “very decent”. For the student response that is equal to the percentage of the acquisition of 88.24%. The result of this research biology modules guided inquiry is very suitable used for students class X SMA.