The purpose of this study was to investigate the expectations and perceptions of Korean mothers living in Singapore of their children’s dual language acquisition. The subjects of this study were eight Korean mothers with young children living in Singapore for more than a year. Their interviews were analyzed according to the Consensual Qualitative Research process. As a result of the analysis, five themes and 21 subcategories were derived. First, before migration, mothers expected that the language environment of Singapore would greatly contribute to the English acquisition of their children. Second, after migration, mothers expected their children to become balanced bilinguals with the expectation to learn a third language. Third, expectations differed depending on their plans to return to Korea. Fourth, while living in Singapore, a child might go through a short silent period, maladjustment, or code mixing. However, mothers recognized that their children were learning dual languages without confusion. Also, they recognized that personality, age, and mother tongue-level influenced English acquisition. Fifth, mothers evaluated the language environment of Singapore very positively. As a result, the multicultural and multilingual society, unique “Singlish”, national language policy, and language curriculum at selective schools in Singapore are considered to be helpful for the bilingual development of children.