Abstract: In order to research the early flowering caused by cold in high latitude tobacco field, alginic acid and KH2PO4, both increase cold resistance of plants, are used to spray tobacco leaves to investigate flowering time, leaf quality and quantities. Results showed that alginic acid and KH2PO4 delayed flowering time of tobacco 8 and 5 days, respectively. The total contents of aroma components in flue-cured tobacco leaves are not obviously affected by both treatments. The maximum production is got from alginic acid treated field, and the quantity is 2100 kg/hm2, increase 16.67% than normal field. The medium and fine levels of flue-cured tobacco leaves account for 97.86% of total production, is 3.7 percent higher than normal levels.