diff --git a/esphome/components/sensor/ppd42x.py b/esphome/components/sensor/ppd42x.py
index 4ceee63c3f..0bfc2c9e39 100644
--- a/esphome/components/sensor/ppd42x.py
+++ b/esphome/components/sensor/ppd42x.py
@@ -55,7 +55,7 @@ def to_code(config):
     ppd = Pvariable(config[CONF_ID], rhs)
     if CONF_PM_2_5 in config:
         conf_02_5 = config[CONF_PM_2_5]
-        for pm_02_5 in get_variable(conf_02_5[CONF_PIN]):
+        for pm_02_5 in get_variable(config[[CONF_PM_2_5][CONF_PIN]]):
             yield
         sensor.register_sensor(ppd.make_pm_02_5_sensor(conf_02_5[CONF_NAME]), pm_02_5)
     if CONF_PM_10_0 in config: