This article examines the extent of political participation by Latino non-citizens across the United States. The only previous national quantitative research on this topic is by Verba, Schlozman and Brady, who found little difference between the participation rates of Latino citizens and non-citizens. Using the Latino National Political Survey, large differences between citizen and non-citizen participation are found. Although Latino non-citizens participated in non-electoral political activities and in non-political civic groups, they were significantly less likely to do so than Latino citizens. Examination of the non-citizen population shows that immigrants who understood politics better, planned on naturalizing, had a stronger ethnic identity, were more familiar with English and were younger were more likely to become involved. The traditional socio-economic measures of education and income as well as length of stay in the United States were non-significant predictors of non-citizen participation.