We analyze the microwave response of Omega-type metamaterial infiltrated with a nematic liquid crystals materials - K15 and BL006. A full-wave analysis technique based on the finite-difference time-domain method (FDTD) was performed using QuickWave 3D electromagnetic solver. Simulation of metamaterial structure with low losses liquid crystals (LC) have been made. LC materials can provide tuning of the metamaterials structure due to reorientation of the liquid crystal director. The main aim of presented work is to determine the influence of LC material on effective refractive index.