Taking half-high bush blueberry ‘Northland’ as test materials，on the basis of mastering blueberry phenophase，the effect of different temperature，humidity，photoperiod on “Northland” flower bud differentiation were studied，the required temperature，humidity，light cycle threshold and optimum conditions of its flower bud differentiation process were determined，to provide technical reference to blueberry cultivation especially for the blueberry planting facilities anti-season cultivation ripening control management.The results showed that，the best condition for early stage of flower bud differentiation of ‘Northland’ blueberry were temperature 20℃，humidity 60%，photoperiod less than 12 hours-short day；the best condition for flower primordium differentiation were temperature 15℃，humidity 80%，photoperiod less than 12 hours-short day；the best condition for sepal primordium differentiation were temperature 15℃，humidity 80%，photoperiod less than 12 hours-short day；the best condition for corolla primordium differentiation were temperature 12℃，humidity 70%，photoperiod less than 12 hours-short day；the best condition for stamen primordium differentiation were temperature 15℃，humidity 80%，photoperiod less than 12 hours-short day；the best condition for carpel primordium differentiation were temperature 20℃，humidity 60%，photoperiod less than 12 hours-short day.