Temperature measurements have become a fundamental activity in manysectors. For example, warehouses and food products require a constanttemperature and this calls for better temperature monitoring technologies areneeded in production and processes.The work's objective is to describe the design and implementation of a low-costIoT-based temperature monitoring system for industries. The system consists ofa network of wireless temperature sensors. Two different units are implementedusing the DS18B20 1-wire digital sensor and the IR non-contact sensorMLX90614. Both sensors are connected to an ESP8266 IoT device that sendsthe data into the cloud via a Wi-Fi connection. The data is represented on theThingSpeak cloud as dashboard figures in real-time and can be viewed at anytime, anywhere.