A simple and high yielding method was developed for the synthesis of derivatives of1H-pyrazolo[3,4-b]-quinolines was obtained from 2-chloroquinolin-3-carbaldehydes, by using hydrazine hydrate at room tempera-ture and at reflux temperature in ethanol as the solvent. This method developed for the synthesis of1H-pyrazolo[3,4-b]-quinolines gave excellent yields.