diff --git a/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/cli/Picocli.java b/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/cli/Picocli.java
index 0e2fdd4de15..3877bfee03c 100644
--- a/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/cli/Picocli.java
+++ b/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/cli/Picocli.java
@@ -225,6 +225,7 @@ public class Picocli {
         if (cliArgs.contains(OPTIMIZED_BUILD_OPTION_LONG) && !wasBuildEverRun()) {
             throw new PropertyException(Messages.optimizedUsedForFirstStartup());
         }
+        warnOnDuplicatedOptionsInCli();
 
         IncludeOptions options = getIncludeOptions(cliArgs, abstractCommand, abstractCommand.getName());
 
@@ -953,4 +954,13 @@ public class Picocli {
         }
     }
 
+    // Show warning about duplicated options in CLI
+    public void warnOnDuplicatedOptionsInCli() {
+        var duplicatedOptionsNames = ConfigArgsConfigSource.getDuplicatedArgNames();
+        if (!duplicatedOptionsNames.isEmpty()) {
+            warn("Duplicated options present in CLI: %s".formatted(String.join(", ", duplicatedOptionsNames)));
+            ConfigArgsConfigSource.clearDuplicatedArgNames();
+        }
+    }
+
 }
diff --git a/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/configuration/ConfigArgsConfigSource.java b/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/configuration/ConfigArgsConfigSource.java
index 7bf1319abc3..13006ff25d8 100644
--- a/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/configuration/ConfigArgsConfigSource.java
+++ b/quarkus/runtime/src/main/java/org/keycloak/quarkus/runtime/configuration/ConfigArgsConfigSource.java
@@ -22,6 +22,7 @@ import static org.keycloak.quarkus.runtime.cli.Picocli.ARG_SHORT_PREFIX;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -52,6 +53,7 @@ public class ConfigArgsConfigSource extends PropertiesConfigSource {
     private static final String CLI_ARGS = "kc.config.args";
     public static final String NAME = "CliConfigSource";
     private static final Pattern ARG_KEY_VALUE_SPLIT = Pattern.compile("=");
+    private static Set<String> duplicatedArgNames;
 
     protected ConfigArgsConfigSource() {
         super(parseArguments(), NAME, 600);
@@ -103,20 +105,29 @@ public class ConfigArgsConfigSource extends PropertiesConfigSource {
     }
 
     private static Map<String, String> parseArguments() {
-        Map<String, String> properties = new HashMap<>();
+        final Map<String, String> properties = new HashMap<>();
+        final Set<String> allPropertiesNames = new HashSet<>();
+        duplicatedArgNames = new HashSet<>();
 
-        parseConfigArgs(getAllCliArgs(), new BiConsumer<String, String>() {
-            @Override
-            public void accept(String key, String value) {
-                PropertyMappers.getKcKeyFromCliKey(key).ifPresent(s -> {
-                    properties.put(s, value);
-                });
+        parseConfigArgs(getAllCliArgs(), (key, value) -> {
+            if (!allPropertiesNames.add(key)) {
+                duplicatedArgNames.add(key);
             }
+            PropertyMappers.getKcKeyFromCliKey(key).ifPresent(s -> properties.put(s, value));
         }, ignored -> {});
 
         return properties;
     }
 
+    public static Set<String> getDuplicatedArgNames() {
+        return Collections.unmodifiableSet(duplicatedArgNames);
+    }
+
+    public static void clearDuplicatedArgNames() {
+        // after handling these duplicates, clear the memory
+        duplicatedArgNames = Collections.emptySet();
+    }
+
     public static void parseConfigArgs(List<String> args, BiConsumer<String, String> valueArgConsumer, Consumer<String> unaryConsumer) {
         for (int i = 0; i < args.size(); i++) {
             String arg = args.get(i);
diff --git a/quarkus/runtime/src/test/java/org/keycloak/quarkus/runtime/cli/PicocliTest.java b/quarkus/runtime/src/test/java/org/keycloak/quarkus/runtime/cli/PicocliTest.java
index 094f7ecb2f2..f3bf23813e3 100644
--- a/quarkus/runtime/src/test/java/org/keycloak/quarkus/runtime/cli/PicocliTest.java
+++ b/quarkus/runtime/src/test/java/org/keycloak/quarkus/runtime/cli/PicocliTest.java
@@ -984,6 +984,43 @@ public class PicocliTest extends AbstractConfigurationTest {
         assertThat(nonRunningPicocli.getErrString(), containsString("Available only when health is enabled"));
     }
 
+    @Test
+    public void duplicatedCliOptions() {
+        var nonRunningPicocli = pseudoLaunch("start-dev", "--http-access-log-enabled=true", "--http-access-log-enabled=false");
+        assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getOutString(), containsString("WARNING: Duplicated options present in CLI: --http-access-log-enabled"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--http-access-log-enabled=true", "--http-access-log-enabled=false", "--db=postgres", "--db=dev-mem");
+        assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getOutString(), containsString("WARNING: Duplicated options present in CLI: --http-access-log-enabled, --db"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev",
+                "--http-access-log-enabled=true", "--http-access-log-enabled=false",
+                "--db=postgres", "--db=dev-mem",
+                "--db-kind-my-store=mariadb", "--db-kind-my-store=dev-mem");
+        assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getOutString(), containsString("Duplicated options present in CLI: --db-kind-my-store, --http-access-log-enabled, --db"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "--non-existing=yes", "--non-existing=no");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getOutString(), not(containsString("WARNING: Duplicated options present in CLI: --non-existing")));
+        assertThat(nonRunningPicocli.getErrString(), containsString("Unknown option: '--non-existing'"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "-Dsome.property=123", "-Dsome.property=456");
+        assertEquals(CommandLine.ExitCode.OK, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getOutString(), containsString("WARNING: Duplicated options present in CLI: -Dsome.property"));
+        onAfter();
+
+        nonRunningPicocli = pseudoLaunch("start-dev", "something-wrong=asdf", "something-wrong=not-here");
+        assertEquals(CommandLine.ExitCode.USAGE, nonRunningPicocli.exitCode);
+        assertThat(nonRunningPicocli.getOutString(), not(containsString("WARNING: Duplicated options present in CLI: something-wrong")));
+        assertThat(nonRunningPicocli.getErrString(), containsString("Unknown option: 'something-wrong'"));
+    }
+
     @Test
     public void httpOptimizedSerializers() {
         var nonRunningPicocli = pseudoLaunch("start-dev");