diff --git a/homeassistant/components/modbus.py b/homeassistant/components/modbus.py
index c8d71af71b4..40ede019c10 100644
--- a/homeassistant/components/modbus.py
+++ b/homeassistant/components/modbus.py
@@ -16,7 +16,7 @@ from homeassistant.const import (
 
 DOMAIN = 'modbus'
 
-REQUIREMENTS = ['pymodbus==1.3.1']
+REQUIREMENTS = ['pymodbus==1.5.2']
 
 # Type of network
 CONF_BAUDRATE = 'baudrate'
diff --git a/requirements_all.txt b/requirements_all.txt
index d94a746c50e..1f478f4bff9 100644
--- a/requirements_all.txt
+++ b/requirements_all.txt
@@ -1122,7 +1122,7 @@ pymitv==1.4.3
 pymochad==0.2.0
 
 # homeassistant.components.modbus
-pymodbus==1.3.1
+pymodbus==1.5.2
 
 # homeassistant.components.media_player.monoprice
 pymonoprice==0.3