The present disclosure provides a semiconductor device structure with fine boron nitride spacer patterns and a method for forming the semiconductor device structure, which can prevent the collapse of the fine patterns. The semiconductor device structure includes a first target structure and a second target structure disposed over a semiconductor substrate. The semiconductor device structure also includes a first boron nitride spacer disposed over the first target structure, wherein a topmost point of the first boron nitride spacer is between a central line of the first target structure and a central line of the second target structure in a cross-sectional view.