This study investigates how cultural identity influences mental health expression and support in online forums by analyzing data from two forums. It compares the mental health expression of individuals from three Asian countries with those from Western countries along dimensions of identity, language use, and support behavior. Findings reveal that individuals from less-represented countries more frequently mention their country in distress, use fewer clinical terms, and offer support to others from the same country. However, interacting on international forums does not impact the use of clinical language over time. The study suggests design improvements for online forums to enhance support quality, particularly for minority users.