Taiwan is facing the arrival of the aging society, the percentage of the elderly population is currently 11.3%. The purpose of this study is using the point of view of active aging to address the major activities associated with public space in the city, by using the questionnaire and observation as research methods to explore interactions between the elderly and their activity needs. This study investigated 220 elderly in Taipei. Our conclusions are as follows: 1. More Xinyi District respondents (54.2%) are satisfiedwith ＂Taipei as an Age-friendly city＂, than Wanhua District respondents (44.4%). 2. Park is the public space most commonly used by the Elderly (18.3%). 3. Among the eleven indicators of public space in an age-friendly city, the three items of Xinyi District bringing most satisfaction are ＂Importance of green space＂ (3.20), ＂Friendly pavements＂ (3.17), and ＂Pleasant and clean environment＂ (3.09) in sequence. The three items of Xinyi District providing least satisfaction are ＂Walkways and cycle paths＂ (2.50), ＂Services for older customers＂ (2.52), and ＂Adequate public toilets＂ (2.62) in sequence. The three items of Wanhua District providing most satisfaction are ＂Accessibility＂ (3.60), ＂Importance of green space＂ (3.52), and ＂Friendly Buildings＂ (3.40) in sequence.The three items of Wanhua District providing least satisfaction are ＂Safe pedestrian crossings＂ (3.09), ＂Services for older customers ＂ (3.11), and ＂Adequate public toilets ＂ (3.17) in sequence. In the future, improvements in the items provoking dissatisfaction will need to be processed quickly in order to create an ＂Age-friendly city＂.