摘要Background International students contribute to the academic and economic vitality of US higher education while facing exacerbated mental health challenges.Little is known about national trends in anxiety,depression,suicidal ideation and mental health service utilisation in this population.Aims This study examined national trends in the prevalence of clinically significant anxiety,depression,suicidal ideation and service utilisation among international students in US higher education from 2015 to 2024.Methods This repeated cross-sectional study analysed annual data from the Healthy Minds Study,a national survey of collegiate mental health,including 44 560 international students.Weighted prevalence estimates were calculated,and multivariable logistic regression models were used to examine temporal trends,controlling for demographic characteristics.Results The weighted annual prevalence of anxiety increased by 78.25％(from 20.46％in 2015-2016 to 36.47％in 2023-2024),depression increased by 73.04％(from 20.44％to 35.37％),suicidal ideation increased by 92.52％(from 5.35％to 10.30％)and service utilisation increased by 45.82％(from 5.26％to 7.67％).In logistic models controlling for demographic characteristics,the increasing trends in anxiety(adjusted odds ratio(aOR)2.21;95％CI 2.07 to 2.36;p＜0.001),depression(aOR 1.93;95％CI 1.80 to 2.06;p＜0.001),suicidal ideation(aOR 1.57;95％CI 1.41 to 1.74;p＜0.001)and service utilisation(aOR 2.01;95％CI 1.79 to 2.26;p＜0.001)remained statistically significant over time.Conclusions The prevalence of anxiety,depression and suicidal ideation nearly doubled among international students from 2015 to 2024,while counselling service utilisation increased at a slower rate,indicating persistent gaps in mental healthcare.These findings suggest the need for proactive interventions,culturally competent services and expanded outreach efforts to bridge the mental health service gap for international students.