Shoot weight of Orostachys japonicus should determine its profitability. The study was done to determine the effect of phosphorus and potassium fertilization (0, 5, 10, 20 kg $P_2O_5$ or $K_2O$ /1000 $m^2$) on its growth, morphological characters, and flowering. Night-break treatment of 2 hours at midnight were done since Aug. 25 when afterward samples were taken every 4 weeks to Nov. 16. Growth, morphological and flowering related characters were measured from each sample. Plant height, inflorescence length, number of leaves including bracts and stem diameter were increased with increased P and K levels. Leaf and bract, floret, shoot and total dry weights showed similar response to the above morphological characters although P fertilization more increased them than K fertilization. Florets were more formed with increased P and K levels but were not flowered due to the night-break treatment, meaning that P and K fertilization had little effect on anthesis of the florets formed.