This study explores the mediating role of meaning in life with respect to the relationship between adult attachment and psychological well-being. This study proposed that because people with insecure attachments have difficulty in connecting with the external world, this may decrease their ability to attain meaning in life, which may in turn diminish their well-being. Two studies (N = 155 and 234, respectively, with age range from 18 to 31) were conducted. Participants completed self-report measures of attachment, well-being and meaning in life. The results consistently revealed a full mediation effect of meaning in life on the relationship between attachment and well-being. The findings suggested that a deeper sense of meaning in life comes from one's connection with the external world, especially with other people.