diff --git a/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp b/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp
index c01fc274f4..76013e28ff 100644
--- a/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp
+++ b/esphome/components/inkbird_ibsth1_mini/inkbird_ibsth1_mini.cpp
@@ -72,7 +72,7 @@ bool InkbirdIbstH1Mini::parse_device(const esp32_ble_tracker::ESPBTDevice &devic
   auto external_temperature = NAN;
 
   // Read bluetooth data into variable
-  auto measured_temperature = mnf_data.uuid.get_uuid().uuid.uuid16 / 100.0f;
+  auto measured_temperature = ((int16_t) mnf_data.uuid.get_uuid().uuid.uuid16) / 100.0f;
 
   // Set temperature or external_temperature based on which sensor is in use
   if (mnf_data.data[2] == 0) {