Pregnant women are at high risk of mood and anxiety disorders, and options for non-pharmacological treatment are limited. Mindfulness-based cognitive therapy (MBCT) has strong evidence among people with mood and anxiety disorders, but limited studies reported the effectiveness of MBCT on perinatal comorbid conditions. This study aimed to examine the effects of an 8-week MBCT intervention on pregnant women with comorbid depression and anxiety. In this randomized controlled study, 38 pregnant women with a diagnosis of depression and varying levels of comorbid anxiety disorders were randomly assigned to either MBCT or a control group. Scores on the Beck Depression Inventory-II, Beck Anxiety Inventory, Emotion Regulation Questionnaire, and Scales of Psychological Wellbeing were used as outcome measures at baseline, after MBCT, and through 1-month follow-up. Intent to treat analyses provided preliminary evidence that MBCT can be effective in reducing depressive and anxiety symptoms and in enhancing the use of adaptive emotion regulation strategies and psychological well-being. Improvements in outcomes were maintained 1 month. Results provide cross-cultural support for MBCT as a treatment for depression and anxiety in pregnant women. This brief and non-pharmacological treatment can be used to improve maternal psychological health.