To provide an ultrasonic urine volume measuring instrument that can highly accurately measure urine volume in the bladder and its temporal changes as needed and that reduces power consumption. In a ultrasonic urine volume measuring instrument (1) including a ultrasound probe (10), a ultrasound controller (21) that controls transmission and reception of ultrasound and its reflected waves, and an arithmetic unit (24) that calculates urine volume in the bladder on the basis of the reflected waves every measurement cycle, the arithmetic unit (24) includes a comparator (24d) that compares the calculated urine volume in the bladder with a certain first threshold. The ultrasound measurement cycle becomes a longer cycle in the case where the urine volume in the bladder compared by the comparator (24d) is less than the first threshold than that in the case where the urine volume is greater than or equal to the first threshold. The ultrasonic urine volume measuring instrument (1) includes a timer unit capable of causing, in the case where the urine volume in the bladder compared by the comparator is less than the first threshold, the arithmetic unit to enter a sleep state during each measurement cycle, and causing the arithmetic unit to recover every measurement cycle.提供可因應必要而高精度地測定膀胱內的尿量及其時間性變化,而且可抑制消費電力的超音波尿量測定器。一種超音波尿量測定器(1),係具備:超音波探頭(10)、控制超音波及其反射波的發送接收的超音波控制部(21)、及依據前述反射波,依每一測定週期來計算出前述膀胱內的尿量的運算部(24),其中,前述運算部(24),係具有比較被計算出之膀胱內的尿量與所定第1臨限值的比較部(24d);超音波的測定週期,係於前述比較部(24d)中被計算出之膀胱內尿量未滿前述第1臨限值時,成為比是前述第1臨限值以上時還長的週期;又具有於前述比較部中被計算出之膀胱內尿量未滿前述第1臨限值時,可於各測定週期之間使前述運算部成為休眠狀態,並於各測定週期使前述運算部復原的計時器部。1‧‧‧超音波尿量測定器10‧‧‧超音波探頭20‧‧‧控制部21‧‧‧超音波控制部22‧‧‧輸入部23‧‧‧記憶部24‧‧‧運算部24a‧‧‧蓄尿量計算部24d‧‧‧第2比較部25‧‧‧輸出部26‧‧‧警報部27‧‧‧顯示部28‧‧‧計時器部100‧‧‧電池101‧‧‧電源控制電路102‧‧‧計時器.時脈電路
