The electric field direction control characteristics of one-dimensional ladder-type double-period fourth generation quasi-periodic structure defect modes with nematic liquid crystal defect layer was studied by transmission matrix method. Relationship between θ, angle of the applied electric field and incident wave direction, and position of defect mode wavelength, quality factor, optical field distribution of spatial position were analyzed. The influence of quality factors of defect modes on light field intensity was discussed. Results show that the positions of defect modes shift to short wave direction with increasing of θ, and the regulation amount of defect modes wavelength is 84 nm. The quality factors of defect modes increase gradually with increasing of θ. The optical field distribution of defect modes exhibit local phenomenon in spatial location. The light field strength of spatial location is gradually enhanced with increasing of θ. Quality factors of defect modes are proportional to the light field strength.