This research article aims to identify students' Behaviours in productive English skills. Descriptive method was applied to have its data obtained from subjects of the research. They were 23 students of English Teacher Training Program at Tadulako University, Palu. Their behaviours have to be appropriate with their interests. The interests should influence behaviours, but many students have interests which have not been appropriate with their behaviours yet. Those are hopefully integrated into behaviours by professional teachers who constantly develop speaking skills and writing. Its results indicate that their behaviours in productive English skills are consistent in speaking skill since their interests of speaking influence their behaviours of speaking and inconsistent in writing skill since their interests of writing do not fully influence their behaviours of writing, so speaking is more interesting than writing. Besides, dialogue is more interesting than monologue so that writing conversation is more than composition. Thus, their behaviours have been appropriate with interests in speaking already but not in writing yet even though naturally their activities of writing English are more than the ones of speaking English since English in Indonesia is a foreign language. This implies to enable students to have behaviours in productive English skills better than before.