The use of the Internet of Things (IoT) is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices. In critical infrastructure domains like oil and gas supply, intelligent transportation, power grids, and autonomous agriculture, it is essential to guarantee the confidentiality, integrity, and authenticity of data collected and exchanged. However, the limited resources coupled with the heterogeneity of IoT devices make it inefficient or sometimes infeasible to achieve secure data transmission using traditional cryptographic techniques. Consequently, designing a lightweight secure data transmission scheme is becoming essential. In this article, we propose lightweight secure data transmission (LSDT) scheme for IoT environments. LSDT consists of three phases and utilizes an effective combination of symmetric keys and the Elliptic Curve Menezes-Qu-Vanstone asymmetric key agreement protocol. We design the simulation environment and experiments to evaluate the performance of the LSDT scheme in terms of communication and computation costs. Security and performance analysis indicates that the LSDT scheme is secure, suitable for IoT applications, and performs better in comparison to other related security schemes.