Wireless Sensor Networks (WSNs) currently appear as an emerging technology and have a promising area in environments that require agility and efficiency in sensing the environment conditions, such as temperature and humidity. However, these devices have limited capability of hardware, therefore, applications that use this technology must save the most of the device's resources, mainly battery. Seeking to increase the WSN lifetime, this project proposes a data fusion protocol that minimizes the amount of messages exchanged in the network and makes communication more efficient.