diff --git a/eth2/types/src/beacon_block.rs b/eth2/types/src/beacon_block.rs
index f823f234e5..709bf65e09 100644
--- a/eth2/types/src/beacon_block.rs
+++ b/eth2/types/src/beacon_block.rs
@@ -61,11 +61,11 @@ impl BeaconBlock {
         }
     }
 
-    /// Returns the `tree_hash_root | update` of the block.
+    /// Returns the `signed_root` of the block.
     ///
     /// Spec v0.6.3
     pub fn canonical_root(&self) -> Hash256 {
-        Hash256::from_slice(&self.tree_hash_root()[..])
+        Hash256::from_slice(&self.signed_root()[..])
     }
 
     /// Returns a full `BeaconBlockHeader` of this block.