Holden’s red hunting hat relates to the theme of innocence in the novel The Catcher in the Rye. One quote that would relate is Holden’s explanation of how he purchased the hat in the first place:
It was this red hunting hat, with one of those very, very long peaks. I saw it in the window of this sports store when we got out of the subway, just after I noticed I'd lost all the goddam foils. It only cost me a buck. The way I wore it, I swung the old peak way around to the back—very corny, I'll admit, but I liked it that way. I looked good in it that way.
Since losing the fencing foils on the subway is a big disappointment for Holden, his purchasing the hat as a spur-of-the-moment decision could be seen as a band-aid on his bruise, or a lollipop after getting a shot at the doctor’s office. The hat has a similar effect. He likes the way he looks wearing it in his unconventional way, which helps to lighten his mood.
Another quote regarding the hat which could reflect the theme of innocence is when Holden settles down to write Stradlater’s descriptive composition for him: “After he left, I put on my pajamas and bathrobe and my old hunting hat, and started writing the composition.” Because the composition is about a baseball glove that belonged to Holden’s late younger brother, Allie, Holden is engrossed in the memories and affection he has for Allie. Holden’s description of the unique fielder’s glove covered in poems written in green ink, and his description of what an intelligent, kind boy Allie was, portrays Allie as an innocent child who died too soon. Allie’s death at such a young age, and Holden’s reminiscence of this time while wearing his hat, exemplifies how the hunting hat symbolically relates to innocence.