Abstract: The effects of sugar concentration,macroelement,paclobutrazol,salicylic acid and culture condition on bulblet formation and enlargement were studied using plantlet of Oriental Lily,'Sorbonne',in test tubes.The results indicated that,at 60 gL-1 sucrose concentration,the most numbers of the bulblets was formed at the rate of 75%.At 120 gL-1 sucrose concentration,the enlargement of micro-bulb was most significant.High macroelement concentrations tended to favor the enlargement as well,but discouraged formation of the bulblet in the test tubes.The 3MS treatment produced the largest bulblets,but the rate of bulblet formation dropped to 14.6%.The addition of 10 mgL-1 paclobutrazol could aid the bulblet formation and enlargement in the test tubes.And,the application of salicylic acid significantly increased the number of the micro-bulbs formed.