Affordances from physical structure and creator’s intentions have been regarded as the determinants of an object’s perceived function. Two experiments were conducted to explore the conditions when creator’s intentions affected judgments of function. Participants rated the plausibility of the two possible functions after an outline drawing of an object and verbal description of creator’s intentions were presented to them. When one of the two functions was easily derived from the drawing (Experiment 1), the function was judged more plausible regardless of creators’ intention. However, the difference between the plausibility ratings of the two functions got smaller when intention did not match the dominant function. When the two functions were equally likely from the drawing (Experiment 2), creators’ intentions affected the perceived function of an object. The results of two experiments suggested that creators’ intentions affect the judgment of function only when affordances are not strong.