diff --git a/substrate/core/client/src/light/backend.rs b/substrate/core/client/src/light/backend.rs
index fcc58e0ad7..ca5c84cae2 100644
--- a/substrate/core/client/src/light/backend.rs
+++ b/substrate/core/client/src/light/backend.rs
@@ -130,6 +130,16 @@ impl<S, F, Block, H> ClientBackend<Block, H> for Backend<S, F> where
 				operation.leaf_state,
 				operation.aux_ops,
 			)?;
+		} else {
+			for (key, maybe_val) in operation.aux_ops {
+				match maybe_val {
+					Some(val) => self.blockchain.storage().insert_aux(
+						&[(&key[..], &val[..])],
+						::std::iter::empty(),
+					)?,
+					None => self.blockchain.storage().insert_aux(::std::iter::empty(), &[&key[..]])?,
+				}
+			}
 		}
 
 		Ok(())
@@ -311,3 +321,21 @@ where
 		None
 	}
 }
+
+#[cfg(test)]
+mod tests {
+	use primitives::Blake2Hasher;
+	use test_client::runtime::Block;
+	use crate::light::blockchain::tests::{DummyBlockchain, DummyStorage};
+	use super::*;
+
+	#[test]
+	fn light_aux_store_is_updated_via_non_importing_op() {
+		let backend = Backend::new(Arc::new(DummyBlockchain::new(DummyStorage::new())));
+		let mut op = ClientBackend::<Block, Blake2Hasher>::begin_operation(&backend).unwrap();
+		BlockImportOperation::<Block, Blake2Hasher>::insert_aux(&mut op, vec![(vec![1], Some(vec![2]))]).unwrap();
+		ClientBackend::<Block, Blake2Hasher>::commit_operation(&backend, op).unwrap();
+
+		assert_eq!(AuxStore::get_aux(&backend, &[1]).unwrap(), Some(vec![2]));
+	}
+}
diff --git a/substrate/core/client/src/light/blockchain.rs b/substrate/core/client/src/light/blockchain.rs
index 82fff6be6f..6cad6c6841 100644
--- a/substrate/core/client/src/light/blockchain.rs
+++ b/substrate/core/client/src/light/blockchain.rs
@@ -174,12 +174,14 @@ pub mod tests {
 
 	pub struct DummyStorage {
 		pub changes_tries_cht_roots: HashMap<u64, Hash>,
+		pub aux_store: Mutex<HashMap<Vec<u8>, Vec<u8>>>,
 	}
 
 	impl DummyStorage {
 		pub fn new() -> Self {
 			DummyStorage {
 				changes_tries_cht_roots: HashMap::new(),
+				aux_store: Mutex::new(HashMap::new()),
 			}
 		}
 	}
@@ -213,12 +215,15 @@ pub mod tests {
 			'c: 'a,
 			I: IntoIterator<Item=&'a(&'c [u8], &'c [u8])>,
 			D: IntoIterator<Item=&'a &'b [u8]>,
-		>(&self, _insert: I, _delete: D) -> ClientResult<()> {
-			Err(ClientErrorKind::Backend("Test error".into()).into())
+		>(&self, insert: I, _delete: D) -> ClientResult<()> {
+			for (k, v) in insert.into_iter() {
+				self.aux_store.lock().insert(k.to_vec(), v.to_vec());
+			}
+			Ok(())
 		}
 
-		fn get_aux(&self, _key: &[u8]) -> ClientResult<Option<Vec<u8>>> {
-			Err(ClientErrorKind::Backend("Test error".into()).into())
+		fn get_aux(&self, key: &[u8]) -> ClientResult<Option<Vec<u8>>> {
+			Ok(self.aux_store.lock().get(key).cloned())
 		}
 	}