diff --git a/contracts/core/04-channel/IBCChannelHandshake.sol b/contracts/core/04-channel/IBCChannelHandshake.sol
index 4cc64e96..57d828f8 100644
--- a/contracts/core/04-channel/IBCChannelHandshake.sol
+++ b/contracts/core/04-channel/IBCChannelHandshake.sol
@@ -55,6 +55,10 @@ contract IBCChannelHandshake is IBCModuleManager, IIBCChannelHandshake, IIBCChan
         }
 
         string memory channelId = generateChannelIdentifier();
+        ChannelStorage storage channelStorage = getChannelStorage()[msg_.portId][channelId];
+        if (channelStorage.channel.state != Channel.State.STATE_UNINITIALIZED_UNSPECIFIED) {
+            revert IBCChannelAlreadyChannelExists();
+        }
         initializeSequences(msg_.portId, channelId);
         emit GeneratedChannelIdentifier(channelId);
 
@@ -130,6 +134,10 @@ contract IBCChannelHandshake is IBCModuleManager, IIBCChannelHandshake, IIBCChan
         );
 
         string memory channelId = generateChannelIdentifier();
+        ChannelStorage storage channelStorage = getChannelStorage()[msg_.portId][channelId];
+        if (channelStorage.channel.state != Channel.State.STATE_UNINITIALIZED_UNSPECIFIED) {
+            revert IBCChannelAlreadyChannelExists();
+        }
         initializeSequences(msg_.portId, channelId);
         emit GeneratedChannelIdentifier(channelId);
 
diff --git a/contracts/core/04-channel/IIBCChannelErrors.sol b/contracts/core/04-channel/IIBCChannelErrors.sol
index aea595c1..81f102cd 100644
--- a/contracts/core/04-channel/IIBCChannelErrors.sol
+++ b/contracts/core/04-channel/IIBCChannelErrors.sol
@@ -5,6 +5,8 @@ import {Height} from "../../proto/Client.sol";
 import {Channel} from "../../proto/Channel.sol";
 
 interface IIBCChannelErrors {
+    error IBCChannelAlreadyChannelExists();
+
     /// @param state channel state
     error IBCChannelUnexpectedChannelState(Channel.State state);