Because the central wavelength of terahertz (THz) pulse is long, the spatial resolution of the THz detection is limited to sub-millimeter due to the diffraction effect. We report a new THz microscopy by attaching an electro-optical crystal directly to a thin generation crystal. By focusing tightly the optical pump beam, the detected spatial resolution can reach several microns. In additior this mechanism cacan avoid the loss of intensity and spectrum components. In this letter, the configuration and characteristics of this device are described in details.