Sex differences have been demonstrated in the acute phase of COVID-19. Women (F) were found to be less prone to develop a severe disease than men (M), but few studies have assessed sex-differences in Long-COVID-19 syndrome. The aim of this prospective/retrospective study was to characterize the long-term consequences of this infection based on sex. For this purpose, we enrolled 223 patients (89 F and 134 M) who were infected by SARS-CoV-2. In the acute phase of the illness, F reported the following symptoms more frequently than M: weakness, dysgeusia, anosmia, thoracic pain, palpitations, diarrhea, and myalgia-all without significant differences in breathlessness, cough, and sleep disturbance. After a mean follow-up time of 5 months after the acute phase, F were significantly more likely than M to report dyspnea, weakness, thoracic pain, palpitations, and sleep disturbance but not myalgia and cough. At the multivariate logistic regression, women were statistically significantly likely to experience persistent symptoms such as dyspnea, fatigue, chest pain, and palpitations. On the contrary, myalgia, cough, and sleep disturbance were not influenced by sex. We demonstrated that F were more symptomatic than M not only in the acute phase but also at follow-up. Sex was found to be an important determinant of Long-COVID-19 syndrome because it is a significant predictor of persistent symptoms in F, such as dyspnea, fatigue, chest pain, and palpitations. Our results suggest the need for long-term follow-up of these patients from a sex perspective to implement early preventive and personalized therapeutic strategies.