diff --git a/homeassistant/components/modbus/__init__.py b/homeassistant/components/modbus/__init__.py
index 12e2273bf88..e98a61257c6 100644
--- a/homeassistant/components/modbus/__init__.py
+++ b/homeassistant/components/modbus/__init__.py
@@ -116,7 +116,12 @@ from .const import (
     UDP,
 )
 from .modbus import ModbusHub, async_modbus_setup
-from .validators import number_validator, scan_interval_validator, struct_validator
+from .validators import (
+    duplicate_entity_validator,
+    number_validator,
+    scan_interval_validator,
+    struct_validator,
+)
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -327,6 +332,7 @@ CONFIG_SCHEMA = vol.Schema(
         DOMAIN: vol.All(
             cv.ensure_list,
             scan_interval_validator,
+            duplicate_entity_validator,
             [
                 vol.Any(SERIAL_SCHEMA, ETHERNET_SCHEMA),
             ],
diff --git a/homeassistant/components/modbus/validators.py b/homeassistant/components/modbus/validators.py
index b59557e58d2..543618e11fd 100644
--- a/homeassistant/components/modbus/validators.py
+++ b/homeassistant/components/modbus/validators.py
@@ -9,9 +9,11 @@ from typing import Any
 import voluptuous as vol
 
 from homeassistant.const import (
+    CONF_ADDRESS,
     CONF_COUNT,
     CONF_NAME,
     CONF_SCAN_INTERVAL,
+    CONF_SLAVE,
     CONF_STRUCTURE,
     CONF_TIMEOUT,
 )
@@ -189,3 +191,35 @@ def scan_interval_validator(config: dict) -> dict:
             )
             hub[CONF_TIMEOUT] = minimum_scan_interval - 1
     return config
+
+
+def duplicate_entity_validator(config: dict) -> dict:
+    """Control scan_interval."""
+    for hub_index, hub in enumerate(config):
+        addresses: set[str] = set()
+        for component, conf_key in PLATFORMS:
+            if conf_key not in hub:
+                continue
+            names: set[str] = set()
+            errors: list[int] = []
+            for index, entry in enumerate(hub[conf_key]):
+                name = entry[CONF_NAME]
+                addr = str(entry[CONF_ADDRESS])
+                if CONF_SLAVE in entry:
+                    addr += "_" + str(entry[CONF_SLAVE])
+                if addr in addresses:
+                    err = f"Modbus {component}/{name} address {addr} is duplicate, second entry not loaded!"
+                    _LOGGER.warning(err)
+                    errors.append(index)
+                elif name in names:
+                    err = f"Modbus {component}/{name}  is duplicate, second entry not loaded!"
+                    _LOGGER.warning(err)
+                    errors.append(index)
+                else:
+                    names.add(name)
+                    addresses.add(addr)
+
+            for i in reversed(errors):
+                del config[hub_index][conf_key][i]
+
+    return config
diff --git a/tests/components/modbus/test_cover.py b/tests/components/modbus/test_cover.py
index 266193294c6..a315d8176ae 100644
--- a/tests/components/modbus/test_cover.py
+++ b/tests/components/modbus/test_cover.py
@@ -235,7 +235,7 @@ async def test_restore_state_cover(hass, mock_test_state, mock_modbus):
                 {
                     CONF_NAME: f"{TEST_ENTITY_NAME}2",
                     CONF_INPUT_TYPE: CALL_TYPE_COIL,
-                    CONF_ADDRESS: 1234,
+                    CONF_ADDRESS: 1235,
                     CONF_SCAN_INTERVAL: 0,
                 },
             ]
diff --git a/tests/components/modbus/test_fan.py b/tests/components/modbus/test_fan.py
index fb65f737d27..821a5cace99 100644
--- a/tests/components/modbus/test_fan.py
+++ b/tests/components/modbus/test_fan.py
@@ -231,7 +231,7 @@ async def test_fan_service_turn(hass, caplog, mock_pymodbus):
                 },
                 {
                     CONF_NAME: f"{TEST_ENTITY_NAME}2",
-                    CONF_ADDRESS: 17,
+                    CONF_ADDRESS: 18,
                     CONF_WRITE_TYPE: CALL_TYPE_REGISTER_HOLDING,
                     CONF_SCAN_INTERVAL: 0,
                     CONF_VERIFY: {},
diff --git a/tests/components/modbus/test_light.py b/tests/components/modbus/test_light.py
index f679883e908..486dfdc64f8 100644
--- a/tests/components/modbus/test_light.py
+++ b/tests/components/modbus/test_light.py
@@ -231,7 +231,7 @@ async def test_light_service_turn(hass, caplog, mock_pymodbus):
                 },
                 {
                     CONF_NAME: f"{TEST_ENTITY_NAME}2",
-                    CONF_ADDRESS: 17,
+                    CONF_ADDRESS: 18,
                     CONF_WRITE_TYPE: CALL_TYPE_REGISTER_HOLDING,
                     CONF_SCAN_INTERVAL: 0,
                     CONF_VERIFY: {},
diff --git a/tests/components/modbus/test_switch.py b/tests/components/modbus/test_switch.py
index 302189001c5..fb929d26caf 100644
--- a/tests/components/modbus/test_switch.py
+++ b/tests/components/modbus/test_switch.py
@@ -245,7 +245,7 @@ async def test_switch_service_turn(hass, caplog, mock_pymodbus):
                 },
                 {
                     CONF_NAME: f"{TEST_ENTITY_NAME}2",
-                    CONF_ADDRESS: 17,
+                    CONF_ADDRESS: 18,
                     CONF_WRITE_TYPE: CALL_TYPE_REGISTER_HOLDING,
                     CONF_SCAN_INTERVAL: 0,
                     CONF_VERIFY: {},