diff --git a/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt b/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt
index 46fe659ae..8e3537675 100644
--- a/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt
+++ b/backend/mirai-console/src/internal/plugin/BuiltInJvmPluginLoaderImpl.kt
@@ -20,6 +20,7 @@ import net.mamoe.mirai.console.internal.util.PluginServiceHelper.loadAllServices
 import net.mamoe.mirai.console.plugin.jvm.*
 import net.mamoe.mirai.console.plugin.loader.AbstractFilePluginLoader
 import net.mamoe.mirai.console.plugin.loader.PluginLoadException
+import net.mamoe.mirai.console.plugin.name
 import net.mamoe.mirai.console.util.CoroutineScopeUtils.childScope
 import net.mamoe.mirai.utils.MiraiLogger
 import java.io.File
@@ -93,12 +94,17 @@ internal object BuiltInJvmPluginLoaderImpl :
         return filePlugins.toSet().map { it.value }
     }
 
+    private val loadedPlugins = ConcurrentHashMap<JvmPlugin, Unit>()
+
     @Throws(PluginLoadException::class)
     override fun load(plugin: JvmPlugin) {
         ensureActive()
 
+        if (loadedPlugins.put(plugin, Unit) != null) {
+            error("Plugin '${plugin.name}' is already loaded and cannot be reloaded.")
+        }
         runCatching {
-            check(plugin is JvmPluginInternal) { "A JvmPlugin must extend AbstractJvmPlugin" }
+            check(plugin is JvmPluginInternal) { "A JvmPlugin must extend AbstractJvmPlugin to be loaded by JvmPluginLoader.BuiltIn" }
             plugin.internalOnLoad(plugin.componentStorage)
         }.getOrElse {
             throw PluginLoadException("Exception while loading ${plugin.description.name}", it)
@@ -106,7 +112,7 @@ internal object BuiltInJvmPluginLoaderImpl :
     }
 
     override fun enable(plugin: JvmPlugin) {
-        if (plugin.isEnabled) return
+        if (plugin.isEnabled) error("Plugin '${plugin.name}' is already enabled and cannot be re-enabled.")
         ensureActive()
         runCatching {
             if (plugin is JvmPluginInternal) {
@@ -118,7 +124,7 @@ internal object BuiltInJvmPluginLoaderImpl :
     }
 
     override fun disable(plugin: JvmPlugin) {
-        if (!plugin.isEnabled) return
+        if (!plugin.isEnabled) error("Plugin '${plugin.name}' is not already disabled and cannot be re-disabled.")
 
         if (MiraiConsole.isActive)
             ensureActive()
diff --git a/backend/mirai-console/src/plugin/loader/PluginLoader.kt b/backend/mirai-console/src/plugin/loader/PluginLoader.kt
index e4b9e863f..22021a7df 100644
--- a/backend/mirai-console/src/plugin/loader/PluginLoader.kt
+++ b/backend/mirai-console/src/plugin/loader/PluginLoader.kt
@@ -76,7 +76,7 @@ public interface PluginLoader<P : Plugin, D : PluginDescription> {
      * @throws PluginLoadException 在加载插件遇到意料之中的错误时抛出 (如找不到主类等).
      * @throws IllegalStateException 在插件已经被加载时抛出. 这属于意料之外的情况.
      */
-    @Throws(PluginLoadException::class)
+    @Throws(IllegalStateException::class, PluginLoadException::class)
     public fun load(plugin: P)
 
     /**