OBJECTIVE To develop a descriptive theory for the weight loss experiences of obese perimenopausal women with metabolic syndrome. BACKGROUND Obesity and metabolic syndrome both pose a threat to the health of perimenopausal women; therefore, understanding perimenopausal women's subjective feelings and experiences is beneficial to establishing effective prevention strategies. However, studies have rarely explored these relevant experiences. METHODS A qualitative study using the grounded theory method to establish a descriptive theory. METHODS Eighteen obese perimenopausal women with metabolic syndrome aged 45-60 years participated in comprehensive interviews. RESULTS 'Crossing the gaps to making life modifications' was the core category, and 'the awareness of weight gain and health alarm' was the antecedent condition. In the weight loss experience, the following three interaction categories were identified: (1) 'experiencing bad feelings,' (2) 'encountering obstacles' and (3) 'making efforts to transition to a new life.' Some women adhered to new life habits through perceiving social support and by using self-incentives. Finally, women enjoyed and mastered self-monitoring of their health in their new life, and practiced new changes as part of their life. However, some participants felt that making changes to their life was too time-consuming. Therefore, these women chose to live with their abnormal health without making changes. CONCLUSIONS Obese perimenopausal women with metabolic syndrome experienced various gaps in their weight loss process. Although they struggled with many obstacles, these women were able to learn from their experiences and face their health challenges. CONCLUSIONS These findings can guide healthcare professionals to provide appropriate interventions to understand the hidden health problems of this particular group of women. Healthcare professionals should develop a set of plans by which women receive a complete weight loss program and support from professionals and family.