This dissertation extends and connects prior research on wage inequality and immigration to the U.S. Focusing on evidences derived from cross-metropolitan comparisons, it finds unique temporal trends and spatial patterns of wage inequality among immigrant workers, identifies wage differentials among immigrant groups by individual characteristics, and evaluates the roles of different labor market conditions in determining changes in immigrant wage inequality and their spatial variations. These findings point to the fact that race and ethnicity and geography are two key factors in understanding immigrant wage inequality. While race and ethnicity play an increasingly important role in determining wage disparities among immigrant workers, wage inequality of immigrant workers also depends on their settlement patterns and labor market conditions in their destinations. Wage inequality among immigrants in the U.S. is a function of different types of metropolitan areas, which serve as urban contexts to accommodate racial and ethnic concentration of immigrant workers and their divergent historical economic incorporation. Using the Integrated Public Use Microdata Sample (IPUMS) data of the Decennial Census for the years 1980, 1990, 2000 and pooled 5-year ACS data in 2009, my empirical analysis shows that immigrants had wider wage gap and higher rates of inequality growth during the past three decades than the native-born workers in the U.S. There was great heterogeneity in urban wage inequality among immigrant workers. But all metropolitan areas experienced a rapid growth in wage inequality since 1980. A decomposition of wage inequality of the overall labor force in the U.S. by nativity shows that immigrant wage inequality and their local income shares both had an impact on the contribution of immigrant wage inequality to wage inequality of the overall labor force. An examination of immigrant wage differentials between educational and racial and ethnic groups finds rapid growths in three-decade wage gaps between college graduates and high-school dropouts and that between White and Hispanic foreign-born workers. Among different sources of growth in immigrant wage inequality, the contribution of residual wage inequality declined moderately while the contribution of race and ethnicity continued to grow rapidly during the past three decades. Finally, focusing on labor market level attributes, panel regression models suggest that city population size, R & D spending, structural shifts from manufacturing to services employment, de-unionization in the labor force all contributed significantly to changes in overall and residual wage inequality among both male and female immigrant workers in U.S. metropolitan areas. To certain extent, geography also explained inter-metropolitan variations in overall wage inequality and in residual wage inequality among immigrant workers. For both genders, wage inequalities among immigrant workers tended to be lower in former immigrant gateway metros than in low-immigrant metros. Major-continuous gateway cities were more likely to have significantly higher levels of residual wage inequality among male immigrant workers than low-immigrant metropolitan areas.