Evaluation of site and foundation seismic effect plays a significant role in the geological engineering investigation. Based on the engineering geological conditions and geotechnical engineering investigation situation in Tianjin, the key problems existing in the evaluation of site and foundation seismic effect are discussed, including the seismic fortification intensity determination, site classification, classification of seismic section, liquefaction estimation, soft soil subsidence, ground stability and suitability evaluation and so on, in order to give reference to geotechnical engineering industry.