Rapid changes in social structure have caused a huge impact on family and created a wide range of family issues. Family is the most important investment for everyone, and it is also an important mission to have a healthy family life. Consequently, the role of family leisure activity becomes more and more significant. The study aimed at discussing the relationship between leisure motivations of family hiking and family constraints, hoping to find the present family hiking situation and the factors affecting participation of family hiking. The framework of the study was based on literature review, and summarized the effects on family leisure activity motivations and constraints. The study sites were DaKeng 6 ~ 10 mountain trails in Taichung County. With the judgment sampling on the family of more than 2 members, the fixed-point questionnaires were distributed for investigation. In return, 335 valid questionnaires that met the response rate of 88% were analyzed by descriptive statistics, ANOVA and multiple regression analysis to explore the factors to participation of family hiking. The findings were summarized as follows: 1. Nuclear family participated in the trail hiking most. Their family life cycle was mainly on the stage of adult and the income is between 25001 to 50000 dollars. 2. Factors affecting family leisure motivations were ranked by importance as "physical fitness", "pressure release", "close to nature," "family needs" and "social needs." 3. Factors affecting family leisure constraints were ranked by importance as "family-member constraints" and "structural constraints." The factor between family members is stronger than external environment, but still remains weak. 4. There was no significant difference between family background and family leisure motivations；Family structure and income showed significant difference to family leisure constraints；Family background showed no significant difference to the participation and regulation of family leisure activities. Family life cycle showed significance difference to the frequency of family leisure participation. 5. Multiple regression results showed that there was significant correlation between leisure motivations of health-related fitness and family life cycle behaviors to leisure participation.