Wireless Sensor Network (WSN) is an infrastructureless network with large number of sensing nodes that can monitor areas such as physical or environmental conditions (i.e., temperature, sound, pressure) to collect and report data to the Base Station (BS). Networks face several challenges like energy, and power. Since the sensor nodes are not battery replaceable, the limited energy resource is a main challenge in facing security for WSNs. Hence, network lifetime becomes a major criteria and can be improved by energy efficient routing and secure energy efficient routing for WSN. Routing protocols that provides an effective design in data gathering are energy efficient cluster-based routing protocols. The existing approach (EE-LEACH) provides a WSN with less energy consumption. However, it concentrates mainly in energy resource, but lacks in providing security resources to the network. This paper presents a proposed Energy Efficient LEACH protocol using lightweight secure LEACH (LS_LEACH), where a broadcast authentication algorithm is integrated to produce authenticity. Moreover, the experimental results show the development of proposed EE_LEACH protocol and existing protocol in terms of system throughput, energy consumption and network lifetime. It is obviously shown that the proposed method will provide better network performance and improves the network lifetime.