diff --git a/core/src/block.rs b/core/src/block.rs
index 3064144854..4a1f4309e1 100644
--- a/core/src/block.rs
+++ b/core/src/block.rs
@@ -32,10 +32,6 @@ impl Block {
         &self.header
     }
 
-    pub fn mut_header(&mut self) -> &mut Header {
-        &mut self.header
-    }
-
     pub fn is_genesis(&self) -> bool {
         self.header.is_genesis()
     }
@@ -102,15 +98,11 @@ impl BlockBuilder {
     }
 
     pub fn uncle(mut self, uncle: UncleBlock) -> Self {
-        *self.inner.mut_header().mut_raw().mut_uncles_count() =
-            self.inner.header().raw().uncles_count() + 1;
         self.inner.uncles.push(uncle);
         self
     }
 
     pub fn uncles(mut self, uncles: Vec<UncleBlock>) -> Self {
-        *self.inner.mut_header().mut_raw().mut_uncles_count() =
-            self.inner.header().raw().uncles_count() + uncles.len() as u32;
         self.inner.uncles.extend(uncles);
         self
     }
diff --git a/core/src/header.rs b/core/src/header.rs
index d1e8775ad8..36300336d3 100644
--- a/core/src/header.rs
+++ b/core/src/header.rs
@@ -138,18 +138,10 @@ impl Header {
         self.raw.uncles_hash
     }
 
-    pub fn raw(&self) -> &RawHeader {
-        &self.raw
-    }
-
     pub fn into_raw(self) -> RawHeader {
         self.raw
     }
 
-    pub fn mut_raw(&mut self) -> &mut RawHeader {
-        &mut self.raw
-    }
-
     pub fn uncles_count(&self) -> u32 {
         self.raw.uncles_count
     }
diff --git a/verification/src/tests/uncle_verifier.rs b/verification/src/tests/uncle_verifier.rs
index 6349502bce..c0674f984c 100644
--- a/verification/src/tests/uncle_verifier.rs
+++ b/verification/src/tests/uncle_verifier.rs
@@ -94,13 +94,12 @@ fn test_uncle_verifier() {
 
     let verifier = UnclesVerifier::new(shared.clone());
 
-    let mut block = BlockBuilder::default()
+    let block = BlockBuilder::default()
         .block(chain1.last().cloned().unwrap())
         .uncle(chain2.last().cloned().unwrap().into())
         .build();
 
-    *block.mut_header().mut_raw().mut_uncles_count() = 0;
-    // Uncles not match uncles_hash
+    // Uncles not match uncles_count
     assert_eq!(
         verifier.verify(&block),
         Err(Error::Uncles(UnclesError::MissMatchCount {
@@ -113,6 +112,7 @@ fn test_uncle_verifier() {
 
     let block = BlockBuilder::default()
         .block(chain1.last().cloned().unwrap())
+        .header(HeaderBuilder::default().uncles_count(1).build())
         .uncle(chain2.last().cloned().unwrap().into())
         .build();
     // Uncles not match uncles_hash