b＞Purpose/b＞ Growth hormone deficiency (GHD) is defined as a serum GH peak 10 ng/mL on provocation with a combination of at least two separate stimulation tests. The Insulin-induced hypoglycemia is the oldest test that has been described to evaluate GH function. However this test is labor intensive, has potential risks for severe hypoglycemia. The aim of this study is to compare two standard provocation tests, insulin and L-dopa, mainly focus on its sensitivity, specificity and safety. b＞Methods/b＞ Clinical data were collected retrospectively from a review of medical records of 120 children who visited the pediatric endocrine clinic at Chonnam National University Hospital for short stature between January 2006 and April 2014. Study subjects underwent GH stimulation test with insulin and L-dopa. Blood samples were obtained at 0, 15, 30, 45, 60, 90, and 120 min after the administration, and the levels of growth hormone were measured. In insulin stimulation test, serial glucose levels were also checked, closely monitoring of the hypoglycemia. b＞Results/b＞ Of the 120 children who underwent GH stimulation test, 83 children (69.1%) were di¬agnosed as GHD and 37 children (30.8%) were diagnosed as idiopathic short stature (ISS). Peak GH levels were achieved at average 45 min after the administration of insulin and L-dopa for GHD group, and 50 min for ISS group. We also compared cross-sectional and cumulative frequency of GH cut-off value of ＞10 ng/mL at each time point during insulin and L-dopa stimulation test in ISS patients. The cumulative frequency at 120 min showed 75.6% to insulin compared with 35.1% to L-dopa.In case of insulin, the specificity was 78.4% and the accuracy was 93.6%, on the other hand, the specificity for L-dopa stimulation test was 29.7%. b＞Conclusion/b＞ Considering the higher specificity of insulin stimulation test (78.4%, compared with L-dopa, 29.7%), and the higher cumulative frequency of GH cut-off values of ＞10 ng/mL in ISS group (75.6%, compared with L-dopa, 35.1%), it would be better to perform insulin stimulation test first, then L-dopa if needed. In that way, in patients with short stature, diagnosis of ISS can be made shortly after a single test, so the hospital day can be shortened and the burden of doing two serial test would be reduced.