In an effort to make a fast and convenient approach for efficient production of recombinant antibody, transient gene expression was performed in human embryonic kidney 293E (HEK293E) cells, which have been widely used as a mammalian host for transient expression of recombinant proteins. Woodchuck hepatitis virus post-transcriptional regulation element (WPRE) was employed to increase the antibody production. Under the influence of WPRE, the antibody production was increased by 5.5-fold through the enhancement of total mRNA levels of HC and LC, and the efficient export of nuclear mRNA into the cytoplasm. Using WPRE, 1.9 mg of cumulative recombinant antibody was obtained in transiently transfected adherent HEK293E cells from one 100 mm dish transfection with 10 mL medium exchange every 3 days for 24 days of cultivation. In addition, the highest recombinant antibody concentration of 81 mg/L was obtained. This simple and efficient approach of antibody production is expected to provide a sufficient amount of antibody for screening experiments.