diff --git a/framework/src/Volo.Abp.AzureServiceBus/Volo.Abp.AzureServiceBus.csproj b/framework/src/Volo.Abp.AzureServiceBus/Volo.Abp.AzureServiceBus.csproj
index 98a67869cf..aef38c1e10 100644
--- a/framework/src/Volo.Abp.AzureServiceBus/Volo.Abp.AzureServiceBus.csproj
+++ b/framework/src/Volo.Abp.AzureServiceBus/Volo.Abp.AzureServiceBus.csproj
@@ -5,6 +5,8 @@
 
     <PropertyGroup>
         <TargetFrameworks>netstandard2.0;netstandard2.1;net7.0</TargetFrameworks>
+        <Nullable>enable</Nullable>
+        <WarningsAsErrors>Nullable</WarningsAsErrors>
         <AssemblyName>Volo.Abp.AzureServiceBus</AssemblyName>
         <PackageId>Volo.Abp.AzureServiceBus</PackageId>
         <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
diff --git a/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/AzureServiceBusMessageConsumer.cs b/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/AzureServiceBusMessageConsumer.cs
index 71143b834e..4417a6ef79 100644
--- a/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/AzureServiceBusMessageConsumer.cs
+++ b/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/AzureServiceBusMessageConsumer.cs
@@ -20,9 +20,9 @@ public class AzureServiceBusMessageConsumer : IAzureServiceBusMessageConsumer, I
     private readonly IExceptionNotifier _exceptionNotifier;
     private readonly IProcessorPool _processorPool;
     private readonly ConcurrentBag<Func<ServiceBusReceivedMessage, Task>> _callbacks;
-    private string _connectionName;
-    private string _subscriptionName;
-    private string _topicName;
+    private string _connectionName = default!;
+    private string _subscriptionName = default!;
+    private string _topicName = default!;
 
     public AzureServiceBusMessageConsumer(
         IExceptionNotifier exceptionNotifier,
@@ -37,7 +37,7 @@ public class AzureServiceBusMessageConsumer : IAzureServiceBusMessageConsumer, I
     public virtual void Initialize(
         [NotNull] string topicName,
         [NotNull] string subscriptionName,
-        string connectionName)
+        string? connectionName)
     {
         Check.NotNull(topicName, nameof(topicName));
         Check.NotNull(subscriptionName, nameof(subscriptionName));
diff --git a/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/ClientConfig.cs b/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/ClientConfig.cs
index 9b9cbd6843..02b8397917 100644
--- a/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/ClientConfig.cs
+++ b/framework/src/Volo.Abp.AzureServiceBus/Volo/Abp/AzureServiceBus/ClientConfig.cs
@@ -5,7 +5,7 @@ namespace Volo.Abp.AzureServiceBus;
 
 public class ClientConfig
 {
-    public string ConnectionString { get; set; }
+    public string ConnectionString { get; set; } = default!;
 
     public ServiceBusAdministrationClientOptions Admin { get; set; } = new();