The carbon nanotubes (CNTs) were prepared by catalytic decompose of benzene using floating transition method at 1100-1200°C. Benzene was used as carbon source and ferrocene as catalyst with thiophene. The carbon nanotubes are straight with diameter 20-50 nm, internal diameter 10-30 nm and length 50-1000 μm. The carbon nanotube and continuous carbon fiber (T300) reinforced unidirectional epoxy resin matrix composites was fabricated. The volune fraction of continuous carbon fiber (first filler) in the composites without second filler (carbon nanotube) was 60%. The mechanical properties of the composites were investigated under bending, shear, and impact loading. The flexural strength and modulus of the composites increased firstly and then decreased with the increasing of carbon nanotube contents in epoxy resin matrix. The flexural strength of the composites reached the maximum value of 1780 MPa when the weight percent of carbon nanotube in epoxy resin matrix was 3%.