As cognitively gifted students may be at risk for motivational problems and underachievement, it is critical to find effective ways to motivate them. Grounded in self-determination theory (SDT) and the literature on teacher beliefs and mindsets, the present study examined whether teachers adapt their motivational teaching style as a function of the cognitive ability of students and which factors can explain the variability in teachers' use of (de)motivating styles among gifted versus typical students. Results of linear mixed modeling among 122 teachers in secondary education (73% female; M[subscript age] = 39.52 years) indicated that teachers made more use of autonomy-supportive and chaotic and less use of controlling and structuring practices towards cognitively gifted, relative to typical, students, with differences in the perceived effectiveness of teaching styles by type of student explaining this variability. Regardless of students' giftedness status, teachers' fixed mindset related positively to the use of a controlling and chaotic style and experience in giftedness education related positively to the use of autonomy support. Misconceptions regarding giftedness did not relate to teachers' motivating style. These results inform prevention efforts aimed at improving teachers' motivating styles, to the benefit of the motivation of both cognitively gifted and typical students.