A terahertz metamaterial filter based on dielectric resonator was proposed. Its structure consisted of a high dielectric constant resonator and a polydimethylsiloxane （PDMS） substrate， and its simulation analysis was carried out by finite element method. The results showed that the filter was insensitive to polarization. The filtering characteristics were explored and the influence of structure parameters on transmission coefficient was studied by using the control variable method. At the same time， part or all of the frequency band could be dynamically adjustable by controlling the change of the dielectric constant of the liquid crystal. In addition， in order to understand the transmission mechanism of the filter， the resonant mechanism was analyzed from two aspects： the effective medium theory and the resonator theory.