diff --git a/nft/src/lib.rs b/nft/src/lib.rs
index 16cff62ff..0387e2618 100644
--- a/nft/src/lib.rs
+++ b/nft/src/lib.rs
@@ -22,21 +22,26 @@
 #![allow(clippy::unused_unit)]
 
 use codec::{Decode, Encode};
-use frame_support::{ensure, pallet_prelude::*, Parameter};
+use frame_support::{
+	ensure,
+	pallet_prelude::*,
+	traits::{Get, MaxEncodedLen},
+	BoundedVec, Parameter,
+};
 use sp_runtime::{
 	traits::{AtLeast32BitUnsigned, CheckedAdd, CheckedSub, MaybeSerializeDeserialize, Member, One, Zero},
 	ArithmeticError, DispatchError, DispatchResult, RuntimeDebug,
 };
-use sp_std::vec::Vec;
+use sp_std::{convert::TryInto, vec::Vec};
 
 mod mock;
 mod tests;
 
 /// Class info
-#[derive(Encode, Decode, Clone, Eq, PartialEq, RuntimeDebug)]
-pub struct ClassInfo<TokenId, AccountId, Data> {
+#[derive(Encode, Decode, Clone, Eq, PartialEq, MaxEncodedLen, RuntimeDebug)]
+pub struct ClassInfo<TokenId, AccountId, Data, ClassMetadataOf> {
 	/// Class metadata
-	pub metadata: Vec<u8>,
+	pub metadata: ClassMetadataOf,
 	/// Total issuance for the class
 	pub total_issuance: TokenId,
 	/// Class owner
@@ -46,10 +51,10 @@ pub struct ClassInfo<TokenId, AccountId, Data> {
 }
 
 /// Token info
-#[derive(Encode, Decode, Clone, Eq, PartialEq, RuntimeDebug)]
-pub struct TokenInfo<AccountId, Data> {
+#[derive(Encode, Decode, Clone, Eq, PartialEq, MaxEncodedLen, RuntimeDebug)]
+pub struct TokenInfo<AccountId, Data, TokenMetadataOf> {
 	/// Token metadata
-	pub metadata: Vec<u8>,
+	pub metadata: TokenMetadataOf,
 	/// Token owner
 	pub owner: AccountId,
 	/// Token Properties
@@ -72,11 +77,22 @@ pub mod module {
 		type ClassData: Parameter + Member + MaybeSerializeDeserialize;
 		/// The token properties type
 		type TokenData: Parameter + Member + MaybeSerializeDeserialize;
+		/// The maximum size of a class's metadata
+		type MaxClassMetadata: Get<u32>;
+		/// The maximum size of a token's metadata
+		type MaxTokenMetadata: Get<u32>;
 	}
 
-	pub type ClassInfoOf<T> =
-		ClassInfo<<T as Config>::TokenId, <T as frame_system::Config>::AccountId, <T as Config>::ClassData>;
-	pub type TokenInfoOf<T> = TokenInfo<<T as frame_system::Config>::AccountId, <T as Config>::TokenData>;
+	pub type ClassMetadataOf<T> = BoundedVec<u8, <T as Config>::MaxClassMetadata>;
+	pub type TokenMetadataOf<T> = BoundedVec<u8, <T as Config>::MaxTokenMetadata>;
+	pub type ClassInfoOf<T> = ClassInfo<
+		<T as Config>::TokenId,
+		<T as frame_system::Config>::AccountId,
+		<T as Config>::ClassData,
+		ClassMetadataOf<T>,
+	>;
+	pub type TokenInfoOf<T> =
+		TokenInfo<<T as frame_system::Config>::AccountId, <T as Config>::TokenData, TokenMetadataOf<T>>;
 
 	pub type GenesisTokenData<T> = (
 		<T as frame_system::Config>::AccountId, // Token owner
@@ -106,6 +122,8 @@ pub mod module {
 		/// Can not destroy class
 		/// Total issuance is not 0
 		CannotDestroyClass,
+		/// Failed because the Maximum amount of metadata was exceeded
+		MaxMetadataExceeded,
 	}
 
 	/// Next available class ID.
@@ -182,6 +200,9 @@ impl<T: Config> Pallet<T> {
 		metadata: Vec<u8>,
 		data: T::ClassData,
 	) -> Result<T::ClassId, DispatchError> {
+		let bounded_metadata: BoundedVec<u8, T::MaxClassMetadata> =
+			metadata.try_into().map_err(|_| Error::<T>::MaxMetadataExceeded)?;
+
 		let class_id = NextClassId::<T>::try_mutate(|id| -> Result<T::ClassId, DispatchError> {
 			let current_id = *id;
 			*id = id.checked_add(&One::one()).ok_or(Error::<T>::NoAvailableClassId)?;
@@ -189,7 +210,7 @@ impl<T: Config> Pallet<T> {
 		})?;
 
 		let info = ClassInfo {
-			metadata,
+			metadata: bounded_metadata,
 			total_issuance: Default::default(),
 			owner: owner.clone(),
 			data,
@@ -226,6 +247,9 @@ impl<T: Config> Pallet<T> {
 		data: T::TokenData,
 	) -> Result<T::TokenId, DispatchError> {
 		NextTokenId::<T>::try_mutate(class_id, |id| -> Result<T::TokenId, DispatchError> {
+			let bounded_metadata: BoundedVec<u8, T::MaxTokenMetadata> =
+				metadata.try_into().map_err(|_| Error::<T>::MaxMetadataExceeded)?;
+
 			let token_id = *id;
 			*id = id.checked_add(&One::one()).ok_or(Error::<T>::NoAvailableTokenId)?;
 
@@ -239,7 +263,7 @@ impl<T: Config> Pallet<T> {
 			})?;
 
 			let token_info = TokenInfo {
-				metadata,
+				metadata: bounded_metadata,
 				owner: owner.clone(),
 				data,
 			};
diff --git a/nft/src/mock.rs b/nft/src/mock.rs
index 915f67561..e1f708a25 100644
--- a/nft/src/mock.rs
+++ b/nft/src/mock.rs
@@ -43,11 +43,18 @@ impl frame_system::Config for Runtime {
 	type OnSetCode = ();
 }
 
+parameter_types! {
+	pub const MaxClassMetadata: u32 = 1;
+	pub const MaxTokenMetadata: u32 = 1;
+}
+
 impl Config for Runtime {
 	type ClassId = u64;
 	type TokenId = u64;
 	type ClassData = ();
 	type TokenData = ();
+	type MaxClassMetadata = MaxClassMetadata;
+	type MaxTokenMetadata = MaxTokenMetadata;
 }
 
 type UncheckedExtrinsic = frame_system::mocking::MockUncheckedExtrinsic<Runtime>;
diff --git a/nft/src/tests.rs b/nft/src/tests.rs
index 1e2654e40..c62354308 100644
--- a/nft/src/tests.rs
+++ b/nft/src/tests.rs
@@ -178,3 +178,18 @@ fn destroy_class_should_fail() {
 		assert_eq!(Classes::<Runtime>::contains_key(CLASS_ID), false);
 	});
 }
+
+#[test]
+fn exceeding_max_metadata_should_fail() {
+	ExtBuilder::default().build().execute_with(|| {
+		assert_noop!(
+			NonFungibleTokenModule::create_class(&ALICE, vec![1, 2], ()),
+			Error::<Runtime>::MaxMetadataExceeded
+		);
+		assert_ok!(NonFungibleTokenModule::create_class(&ALICE, vec![1], ()));
+		assert_noop!(
+			NonFungibleTokenModule::mint(&BOB, CLASS_ID, vec![1, 2], ()),
+			Error::<Runtime>::MaxMetadataExceeded
+		);
+	});
+}
diff --git a/rewards/src/lib.rs b/rewards/src/lib.rs
index cd2acfb11..7d41ca823 100644
--- a/rewards/src/lib.rs
+++ b/rewards/src/lib.rs
@@ -5,7 +5,7 @@ mod mock;
 mod tests;
 
 use codec::{FullCodec, HasCompact};
-use frame_support::pallet_prelude::*;
+use frame_support::{pallet_prelude::*, traits::MaxEncodedLen};
 use orml_traits::RewardHandler;
 use sp_runtime::{
 	traits::{AtLeast32BitUnsigned, MaybeSerializeDeserialize, Member, Saturating, Zero},
@@ -17,7 +17,7 @@ use sp_std::{
 };
 
 /// The Reward Pool Info.
-#[derive(Clone, Encode, Decode, PartialEq, Eq, RuntimeDebug, Default)]
+#[derive(Clone, Encode, Decode, PartialEq, Eq, RuntimeDebug, Default, MaxEncodedLen)]
 pub struct PoolInfo<Share: HasCompact, Balance: HasCompact> {
 	/// Total shares amount
 	#[codec(compact)]