diff --git a/Cargo.lock b/Cargo.lock
index 0b35d30c61..dee7f85e5c 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -862,6 +862,16 @@ dependencies = [
  "redox_syscall",
 ]
 
+[[package]]
+name = "libyml"
+version = "0.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3302702afa434ffa30847a83305f0a69d6abd74293b6554c18ec85c7ef30c980"
+dependencies = [
+ "anyhow",
+ "version_check",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.11.0"
@@ -1035,6 +1045,7 @@ dependencies = [
  "regex",
  "serde",
  "serde_json",
+ "serde_yml",
  "sha2",
  "tempfile",
  "toml",
@@ -1705,6 +1716,21 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_yml"
+version = "0.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59e2dd588bf1597a252c3b920e0143eb99b0f76e4e082f4c92ce34fbc9e71ddd"
+dependencies = [
+ "indexmap",
+ "itoa",
+ "libyml",
+ "memchr",
+ "ryu",
+ "serde",
+ "version_check",
+]
+
 [[package]]
 name = "sha1"
 version = "0.10.6"
diff --git a/Cargo.toml b/Cargo.toml
index 2d97562e42..20af504772 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -131,6 +131,7 @@ default = ["watch", "serve", "search"]
 watch = ["dep:notify", "dep:notify-debouncer-mini", "dep:ignore", "dep:pathdiff", "dep:walkdir"]
 serve = ["dep:futures-util", "dep:tokio", "dep:axum", "dep:tower-http"]
 search = ["mdbook-html/search"]
+frontmatter = ["mdbook-html/frontmatter"]
 
 [[bin]]
 doc = false
diff --git a/crates/mdbook-html/Cargo.toml b/crates/mdbook-html/Cargo.toml
index 7ca8b08090..931734d3bc 100644
--- a/crates/mdbook-html/Cargo.toml
+++ b/crates/mdbook-html/Cargo.toml
@@ -23,6 +23,7 @@ pulldown-cmark.workspace = true
 regex.workspace = true
 serde.workspace = true
 serde_json.workspace = true
+serde_yml = { version = "0.0.12", optional = true }
 sha2.workspace = true
 tracing.workspace = true
 
@@ -35,3 +36,4 @@ workspace = true
 
 [features]
 search = ["dep:elasticlunr-rs"]
+frontmatter = ["dep:serde_yml"]
diff --git a/crates/mdbook-html/src/frontmatter.rs b/crates/mdbook-html/src/frontmatter.rs
new file mode 100644
index 0000000000..08b02e8eb7
--- /dev/null
+++ b/crates/mdbook-html/src/frontmatter.rs
@@ -0,0 +1,101 @@
+//! Frontmatter parsing support for mdBook.
+//!
+//! Extracts YAML frontmatter from markdown content and injects
+//! Open Graph / Twitter Card metadata into the Handlebars template context.
+
+use serde::Deserialize;
+use serde_json::json;
+
+/// Parsed YAML frontmatter fields.
+#[derive(Deserialize, Debug)]
+pub(crate) struct FrontMatter {
+    /// Page title for OG/Twitter meta tags.
+    pub title: String,
+    /// Page description for OG/Twitter meta tags.
+    pub description: String,
+    /// Featured image URL for OG/Twitter meta tags.
+    pub featured_image_url: String,
+}
+
+/// Strips YAML frontmatter (between `---` markers) from content,
+/// returning the content without the frontmatter block.
+pub(crate) fn strip_frontmatter(content: &str) -> String {
+    let trimmed = content.trim_start();
+    if !trimmed.starts_with("---") {
+        return content.to_string();
+    }
+    // Find the closing `---` after the opening one
+    let after_open = &trimmed[3..];
+    if let Some(end) = after_open.find("\n---") {
+        // Skip past the closing `---` and any trailing newline
+        let rest = &after_open[end + 4..];
+        rest.trim_start_matches('\n').to_string()
+    } else {
+        content.to_string()
+    }
+}
+
+/// Parses YAML frontmatter from content and injects OG metadata
+/// into the Handlebars template context data map.
+pub(crate) fn inject_frontmatter_data(
+    content: &str,
+    data: &mut serde_json::Map<String, serde_json::Value>,
+) {
+    let trimmed = content.trim_start();
+    if !trimmed.starts_with("---") {
+        return;
+    }
+    let after_open = &trimmed[3..];
+    let Some(end) = after_open.find("\n---") else {
+        return;
+    };
+    let yaml_str = &after_open[..end];
+
+    match serde_yml::from_str::<FrontMatter>(yaml_str) {
+        Ok(fm) => {
+            data.insert("is_frontmatter".to_owned(), json!(true));
+            data.insert("og_title".to_owned(), json!(fm.title));
+            data.insert("og_description".to_owned(), json!(fm.description));
+            data.insert("og_image_url".to_owned(), json!(fm.featured_image_url));
+        }
+        Err(e) => {
+            eprintln!("Frontmatter: deserialization error: {e:?}");
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_strip_frontmatter() {
+        let input = "---\ntitle: \"Hello\"\n---\n# Content";
+        assert_eq!(strip_frontmatter(input), "# Content");
+    }
+
+    #[test]
+    fn test_strip_no_frontmatter() {
+        let input = "# Just content";
+        assert_eq!(strip_frontmatter(input), "# Just content");
+    }
+
+    #[test]
+    fn test_inject_frontmatter_data() {
+        let input = "---\ntitle: \"My Title\"\ndescription: \"My Desc\"\nfeatured_image_url: \"https://example.com/img.png\"\n---\n# Content";
+        let mut data = serde_json::Map::new();
+        inject_frontmatter_data(input, &mut data);
+        assert_eq!(data["is_frontmatter"], json!(true));
+        assert_eq!(data["og_title"], json!("My Title"));
+        assert_eq!(data["og_description"], json!("My Desc"));
+        assert_eq!(data["og_image_url"], json!("https://example.com/img.png"));
+    }
+
+    #[test]
+    fn test_inject_no_frontmatter() {
+        let input = "# Just content";
+        let mut data = serde_json::Map::new();
+        inject_frontmatter_data(input, &mut data);
+        assert!(!data.contains_key("is_frontmatter"));
+    }
+}
diff --git a/crates/mdbook-html/src/html/mod.rs b/crates/mdbook-html/src/html/mod.rs
index 8a70700f7e..626ffeeeb6 100644
--- a/crates/mdbook-html/src/html/mod.rs
+++ b/crates/mdbook-html/src/html/mod.rs
@@ -96,7 +96,11 @@ pub(crate) fn build_trees<'book>(
             let path = ch.path.as_ref().unwrap();
             let html_path = ch.path.as_ref().unwrap().with_extension("html");
             let options = HtmlRenderOptions::new(path, html_config, edition);
-            let tree = build_tree(&ch.content, &options);
+            #[cfg(feature = "frontmatter")]
+            let chapter_content = crate::frontmatter::strip_frontmatter(&ch.content);
+            #[cfg(not(feature = "frontmatter"))]
+            let chapter_content = ch.content.clone();
+            let tree = build_tree(&chapter_content, &options);
 
             ChapterTree {
                 chapter: ch,
diff --git a/crates/mdbook-html/src/html_handlebars/hbs_renderer.rs b/crates/mdbook-html/src/html_handlebars/hbs_renderer.rs
index 8edac3cace..ef39aef145 100644
--- a/crates/mdbook-html/src/html_handlebars/hbs_renderer.rs
+++ b/crates/mdbook-html/src/html_handlebars/hbs_renderer.rs
@@ -115,6 +115,10 @@ impl HtmlHandlebars {
         nav("previous", prev_ch);
         nav("next", next_ch);
 
+        // Inject frontmatter OG metadata into template context
+        #[cfg(feature = "frontmatter")]
+        crate::frontmatter::inject_frontmatter_data(&ch.content, &mut ctx.data);
+
         // Render the handlebars template with the data
         debug!("Render template");
         let rendered = ctx.handlebars.render("index", &ctx.data)?;
diff --git a/crates/mdbook-html/src/lib.rs b/crates/mdbook-html/src/lib.rs
index 9bb7f00851..d012d395dc 100644
--- a/crates/mdbook-html/src/lib.rs
+++ b/crates/mdbook-html/src/lib.rs
@@ -5,4 +5,7 @@ mod html_handlebars;
 pub mod theme;
 pub(crate) mod utils;
 
+#[cfg(feature = "frontmatter")]
+pub(crate) mod frontmatter;
+
 pub use html_handlebars::HtmlHandlebars;