BACKGROUND: Population aging is now a universal trend. Many elderly persons can only conduct limited and short time walking because of age-related skeletal muscle decline of the lower limbs. The wearable device for walking assistance is beneficial to improve the life quality of the elderly. OBJECTIVE: This study aimed to propose a soft exosuit for walking assistance of the elderly and verify its feasibility. METHODS: The wearable structure and control strategy were presented. The performance of the soft exosuit was tested by force tracking evaluation and metabolic cost test. RESULTS: The mean error of the measured and target peak force was 1.1%. The metabolic cost with assistance on while wearing the exosuit was reduced by 9.2% compared with that in locomotion assistance off. The reduction of assistance on was 7.1% compared with no exosuit. CONCLUSIONS: The proposed soft exosuit has the potential to improve the walking efficiency of the elderly.