Though ultrafast quantum light has several virtues for quantum information processings, difficult efficient homodyne detection restricts to use in practice. Here, we propose a method to improve the detection efficiency of ultrafast homodyne detection by using the temporal correlations in the detector response. A weighted sum of the time varying voltage signal provides the quadrautre, and the optimal weight stems from the temporal response of the detector. From this method, the optimal temporal weight enhances the clearance by 3dB, achieving 17.2dB. We observed the increase of the squeezing level of the squeezed state experimentally and expect the improvement of the measurement of nonclassical properties, such as Wigner negativity.