To identify determinants of the initiation and duration of breastfeeding by Chinese Australian mothers, a cross-sectional survey of 506 Mandarin-speaking women in Perth, Western Australia, was conducted. Doctors' support of breastfeeding was positively associated with the initiation of breastfeeding both in the mothers' home countries (odds ratio [OR], 9.94; 95% confidence interval [CI], 3.17-31.18) and in Australia (OR, 16.78; 95% CI, 7.12-39.55) and with duration. Mother's level of education was positively associated with the initiation of breastfeeding in the mother's home country (OR, 3.04; 95% CI, 1.36-6.80) and positively associated with the duration of breastfeeding both in the mother's home country and Australia. Father's preference for breastfeeding was positively associated with the initiation of breastfeeding of the mother giving birth in Australia (OR, 4.96; 95% CI, 1.93-12.66). Health professionals can provide invaluable support for mothers initiating and continuing breastfeeding in this population. Prenatal education also needs to emphasize the ways in which fathers can support and contribute to breastfeeding.