This study uses data from the Programme for International Student Assessment 2012 to compare the educational efficiency of mathematical literacy and explore the educational equality of mathematics with educational efficiency across four ethnically Chinese regions, including Taiwan (containing seven cities with a population greater than 1 million), Shanghai, Hong Kong, and Singapore. Data envelopment analysis and decomposition of efficiency revealed that Taiwan and Shanghai have the highest overall efficiency (the total of the regional, school, and individual levels), regional plus school efficiency (the total of the regional and school levels), and regional system efficiency. However, Taiwan and Shanghai have the most inefficiency at the individual level, and Hong Kong has the most inefficiency at the regional level. At the school level, there was no significant difference in terms of inefficiency among the four regions. Regarding educational equality among the four regions, there were significant differences in educational inefficiency at the individual, school, and regional levels between students with high and low overall educational efficiency. Specifically, at the individual level, Taiwan had the largest inefficiency difference between students with high and low overall efficiency, followed by Shanghai. At the school level, Singapore had the largest inefficiency difference, followed by Taiwan. At the regional level, only Shanghai had a significant difference in inefficiency. In summary, although Taiwan is one of the top two of these four regions in terms of the educational efficiency of mathematical literacy, it has the most educational inefficiency at the individual level and higher inefficiency differences at the individual and school levels between students with high and low overall efficiency. This indicates that Taiwan can still improve its educational efficiency.