Aim:  To determine the predictors of Japanese long‐term care insurance system (LTCI) certification. Methods:  Care needs of 784 persons aged 65–84 were followed through LTCI over 5 years. Each participant's score was divided into quartiles according to handgrip strength and one‐leg standing time with eyes open. Cox proportional hazard models were conducted for the onset of certification of LTCI. Results:  Over the 5‐year period 64 women (14%) and 30 men (9%) were certified. Adjusted hazard ratios for certification were significantly higher for those of the lowest groups of one‐leg standing time with eyes open at baseline than those in the highest groups, but no significance was found for handgrip strength. Other predictors were age and low social activity for women; and living alone and diabetes for men. Conclusions:  One‐leg standing time with eyes open predicts the onset of care‐need certification in older people.