Methyl tert-butyl ether (MTBE) is an oxygenate additive used to increase the gasoline octane number. Trichloroethene (TCE) is a chlorinated aliphatic hydrocarbon (CAH) that has been used for cleaning and degreasing such diverse products as aircraft engines, automobile parts, and clothing in both military and civilian sectors. Contamination of groundwater with MTBE is often accompanied by chlorinated aliphatic organics (TCE). In this study, a pure culture identified as Paracoccus sp. was originally enriched and isolated from sludge samples from a regional wastewater treatment plant in Taipa, Macau, China. This strain uses MTBE as the sole carbon source while co-metabolizes TCE. The objective of this study is to investigate the bio-removal kinetics of MTBE/TCE mixture using Paracoccus sp. and the improvement of the contaminants removal efficiencies by employing waste silica gel as a matrix for microorganism immobilization. The effects of different concentrations of MTBE and TCE on the bio-removal efficiencies were investigated. The result showed that when MTBE and TCE concentration were higher than 40 mg l -1 and 20 mg l -1 , respectively, the removal efficiencies would be inhibited. The effects of pH and temperature on MTBE and TCE removal rates were further analyzed. The V adsorption kinetics of contaminants on silica gel was also evaluated and the adsorption capacity of MTBE (50 mg l -1) and TCE (50 mg l -1) were 0.42 mg g -1 and 0.65 mg g -1 , respectively. In immobilized system, 20 mg l -1 TCE was removed to non-detectable level while the highest removal efficiency obtained for 40 mg l -1 MTBE was 70.2±3.1%.