This study explores the effect size of the association between students’ economic, social and cultural status (ESCS) and mathematics literacy, and the effect size of national income on the association between students’ ESCS and mathematics literacy. 557,754 samples from 78 countries (including Taiwan) were collected from the Program for International Student Assessment (2022). The meta-analysis showed that the average effect size of the association between ESCS and mathematics literacy in 78 countries was 0.38, which was a low effect size. Among them, the effect size of the association between ESCS and mathematics literacy in 3 countries was higher than 0.50. The highest country is Slovak; 64 countries had effect sizes between 0.31 and 0.49, and 11 countries had effect sizes below 0.30. The effect size of Taiwan was 0.41, and the explained variation is 16.56%. The lowest effect sizes were found in Cambodia and Uzbekistan, which were 0.09 and 0.14 respectively. The effect sizes for countries in Europe, America, Asia, and Oceania had significant effects. The Europe, America and Oceania were higher than those in Asian countries, with Asian countries having the lowest effect sizes. The higher the national income of country, the larger the effect size associated with ESCS and mathematics literacy. Representing national income will increase the effect size of the correlation between students’ ESCS and mathematics literacy. If schools want to improve students’ mathematics literacy, they should pay attention to students’ home learning resources, and the government should improve national income.