An improved urine collection bag assembly is presented. The improved urine collection bag assembly of the present invention features a one-way flow control valve to prevent the backflow of urine into a urinary catheter and subsequently, into a patient's bladder. The improved urine collection bag also features at a lower end a urine sampling valve. In the exemplary embodiment, the one-way flow control valve is a flap style valve and the sampling valve is a slider style valve.
