Background and aims: Internet gaming disorder (IGD) has been mainly studied among adolescents, and no research to date has examined its prevalence in general Chinese adult populations. This study estimated the prevalence of probable IGD in community-dwelling adults in Macao, China. Associations between IGD and psychological distress (i.e., depression and anxiety) as well as IGD and character strength (i.e., psychological resilience and purpose in life) were also tested. Methods: A random, representative sample of 1,000 Chinese residents (44% males; mean age = 40.0) was surveyed using a telephone poll design from October to November 2016. Results: The estimated prevalence of probable IGD was 2.0% of the overall sample and 4.3% among the recent gamers (n = 473), with no statistically significant sex and age effects observed (p > .05). The two most prevalent IGD symptoms were mood modification and continued engagement, despite negative consequences. Probable IGD respondents were more vulnerable to psychological distress (25.0% and 45.0% for moderate or above levels of depression and anxiety, respectively) than their non-IGD counterparts. They also reported a lower level of psychological resilience than non-IGD respondents. No significant buffering effect of the two character strength variables on the distress-IGD relationship was found. Discussion and conclusions: These results provide empirical evidence that IGD is a mental health threat not only to adolescents but also to adults. IGD was significantly associated with psychological distress, which should be addressed in conjunction with IGD symptoms in interventions. Inclusion of gamers of both sexes and different age groups in future prevention programs is also recommended.