Introduction <p>Although prior Western research has identified status-based stressors and examined intra-minority stress (i.e., stresses that stem from within the sexual minority community) within the gay community, few studies have explored intra-minority stress among lesbians or considered its cultural context. This study examined lesbian and bisexual intra-minority stress in Chinese cultural context.</p> Methods <p>We conducted semi-structured interviews (<i>n</i> = 21) to develop the items of the Lesbian and Bisexual Intra-Minority Stress Scale (LBIMSS) and confirmed its reliability, structural stability, convergent validity, concurrent validity, and measurement invariance across sexual orientation (<i>n =</i> 397; data were collected in 2023).</p> Results <p>Psychometric analysis yielded a 22-item version of the LBIMSS with a confirmed three-factor structure: Status-Based Evaluation, Relationship Difficulties, and Exclusion. Cronbach’s <i>α</i> and McDonald’s <i>ω</i> values range from 0.84 to 0.94. All three LBIMSS subscales demonstrated significant positive correlations with minority stress and mental health problems (<i>r</i> = .27–0.43, <i>p</i> &lt; .001). Measurement invariance was established across sexual orientation groups (lesbian and bisexual individuals).</p> Conclusion <p>This study identifies intragroup stress as a significant and distinct stressor affecting lesbian and bisexual women in China. The newly developed LBIMSS demonstrates robust psychometric properties, with excellent internal consistency, convergent validity, and factorial validity, establishing its utility for future research on minority stress dynamics within sexual minority women community.</p> Policy Implications <p>The empirical evidence can contribute to a better understanding of the stress structure of sexual minority, and provide a new reference direction for related mental health services.</p>