Baby boomers in Taiwan benefit from better health, economic conditions, and education in comparison to older generations. The participants in this study were older adult learners from the baby boom generation. This study aimed to examine their retirement decisions, adaptation, and learning processes. A qualitative research approach was employed in this study. Data were collected via semi-structured interviews. Thirty-one individuals, consisting of 15 men and 16 women aged 55-68 years, were interviewed. The research results showed that the interviewees' retirement decisions involved an awareness of retirement timing, and in addition, four approaches to retirement decisions were identified, namely, straightforward decision making, retirement planning, hesitancy, and involuntary retirement. Each decision approach would lead to various losses and gains. The background of baby boomers provided them with high adaptability and the motivation to learn and change. The retirement adaptation process presented goals related to health, learning, and contributions. Learning participation and service learning allowed the interviewed baby boomers to feel joy from learning, forget about their age, and maintain positive attitudes. The results of this study can provide workers engaged in the field of older adult education with a reference for the formulation of policies and projects related to retirement transition and learning.