urodynamic investigation was performed in 31 female patients with voiding difficulty.The result shows:Atony of bladder 11 cases (35 %). High pressure of urethra 14 cases(45 %). Atony of bladder accompaning high pressure of urethra 6 cases (19%). P - Q plot showed: bladder outlet obstruction 14 cases (58 %) Urodynamic investigation is an importent method for the diagnosis and therapy of voiding defficulty in female paticents.