Background: Sexuality is an important part of health-related quality of life. To ensureadequate supportive interventions, valid and reliable instruments specific to sexualchanges and adjustments after cancer treatment are needed. Objectives: The aims ofthis study were to test the psychometric properties of the Sexual AdjustmentQuestionnaire-Swedish version II (SAQ-SII) in patients treated for diffuse large B-celllymphoma and to describe and explore patients' experiences of sexuality after treatment.Methods: A cross-sectional study was conducted in 2019, using SAQ-SII and datafrom the National Quality Registry for Leukemia–subregistry for Lymphoma, whichincluded 257 patients (25% response rate).An exploratory factor analysis was performedfor psychometric evaluation. Internal consistency was assessed by Cronbach's α.Independent t tests, analysis of variance, and multiple regression were used to describepatients' experiences of sexuality. Results: The exploratory factor analysis resulted in a4-factor structure, explaining 65.7% of the total scale variance (SAQ-SII). The Cronbach'sα for the SAQ-SII was 0.88 and varied between 0.70 and 0.89 across subscales.Sexuality was affected in various ways and extent. Sexual Interest was most affected,whereas Sexual Function was least affected. Being male, of younger age, withoutcomorbidities, and in a relationship were associated to a higher Sexual Interest.Conclusions: The SAQ-SII is a valid and reliable instrument to measure changes andadjustments in sexuality in patients treated for lymphoma. Implications for Practice:Assessments of sexuality in a broad sense should be an integrated part of cancer care toensure timely interventions for those who need and want support.