Over more than 20 years of development， the well intersection method has been widely used in solution mining， such as salt extraction， soda extraction； however， in the production process of brine extraction well sets， well clogging often occurs due to various causes. Four pairs of brine well sets in Ningjin salt field have been blocked for many times since they were put into production. In view of the frequent blockage， in reference to various accidents encountered in the drilling and workover processes and the relevant data from brine extraction， and with careful analysis and summary， the causes of well clogging and the preventive measures for Ningjinshi salt field are expounded in terms of squeeze-breaking of casing due to salt bed creeping， sedimentation of insolubles and salt crystallization， so as to provide guidance and suggestions for well workover and new brine well construction in the future.