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Using daily precipitation data, conventional data, sea surface temperature data, and NCEP/ NCAR reanalysis data from 2000 to 2013, the characteristics and causality of cold airflow snowfall in the Laizhou Bay are analyzed. The results show that the snowfall intensity is small, and the moderate and heavy snow are mainly concentrated in the eastern region of the Laizhou Bay. Duration of snowfall is short within 12 hours. Coldairflow snowfall happens more frequently in the east and less in the west of the Laizhou Bay and their interannual variation are obvious. Marked periodic variation of 6 to 7 years is found. Coldairflow snowfall often occurs in January, especially from the last tenday of December to the first tenday of January and mainly around 08:00 in the morning. There is a positive correlation between the annual cold air activity index and the number of cold airflow snowfall events. There are obvious temperature thresholds at <850 hPa levels during coldairflow snowfall events. Coldairflow snowfall happens less at too high or too low sea surface temperature and airsea temperature difference over the Laizhou Bay, and the ground temperature threshold (at 2 m) is below 5 ℃, which is higher than the inland snowfall threshold. Coldairflow snowfall often happens in the northwest airflow behind a trough (including behind eddy) at 500 hPa and the northwest winds at 700 hPa and 850 hPa, and there exist three circumfluence situations: northwest, north, and northeast winds at 925 hPa and 1000 hPa.