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Based on the radar composite reflectivity factor data and thunderstorm gale observation data in North China from 2013 to 2017, a total of 27 strong squall line processes are identified, and their spatial and temporal distribution, development and movement characteristics are statistically analyzed. The results show that the most concentrated months of the strong squall lines are from late July to early August in North China, and the strongest hours are concentrated from 16:00 to 22:00. Most initial 40 dBz echo locations are near the junction of Shanxi, Inner Mongolia and Hebei. Most strong squall lines are formed in Beijing, Tianjin and Hebei. The area from eastern Shanxi Province to western Hebei Province is the concentrated area of the strong squall lines, with the longest length of more than 400 km and a maintenance duration of more than 7 hours. The strong squall lines with an initial echo time of 02:00-07:59 have the longest average formation duration, while those with an initial echo time of 14:00-19:59 have the shortest average formation duration. There is good correspondence between the longest length of the strong squall lines and their development and maintenance duration. The strong squall lines with an initial echo time of 14:00-19:59 move a short distance in the formation period but a long distance in the development period, while the strong squall lines with an initial echo time of 02:00-07:59 are opposite. Most of the strong squall lines move faster in the development period than in the formation period.