In this paper, miniaturized four-element Multiple Inputs Multiple Outputs (MIMO) antenna, with enhanced radiation efficiency, is designed and simulated. This configuration is composed of four T-shaped radiating elements with reduced ground plane and stub having a compact size of 25mm × 25mm × 1.6mm. These four-element are placed orthogonal to each other to produce higher isolation between ports. The proposed antenna exhibits wide impedance bandwidth from 7.8 GHz to 16.5 GHz with radiation efficiency of 92 %. The performance of antenna is analyzed in term of various parameters such as S-parameters (< −10 dB), low mutual coupling (< −15 dB), radiation pattern and diversity criteria that render antenna applicable for X-band and Ku-band.