Abstract: Salt deposition in fractionator is a key problem affecting long-term stable operation of catalytic cracking unit. It will increase the pressure drop of the fractionator, exhaust the top circulating pump, increase the dry point of gasoline and even cause the flushing of the fractionator. The causes of salt deposition in fractionator of catalytic cracking unit was analyzed, some technical measures and effects in production and research was introduced in recent years, mainly including: (1) desalting of catalytic raw materials; (2) online water washing of fractionator; (3) optimization of top circulation process of fractionator; (4) top circulation dehydration of fractionator; (5) addition of ammonium salt dispersant. The advantages and disadvantages of various methods were analyzed. By adopting the corresponding technical measures, the problem of salt deposition in fractionator was effectively alleviated or solved, which plays a positive role in long-term stable operation of catalytic cracking unit.