The call for "mathematics for all" reaffirms the belief that all students should have equal access, equal educational experiences, and equal educational outcomes. Existing gap in students' mathematics achievement have long been coupled with the demographic categories of race and ethnicity, culture and language, SES and social class, gender and disabilities. Standards-based reform in mathematics education has a goal of high academic standards for all students. The literature review of research on equity implications for mathematics learning outcomes in the context of standards-based reform is presented. The purpose of this paper is to examine the effects of various equity variables on mathematics outcomes. The review analyzes the factors that contribute to mathematics achievement gap in terms of standards-based reform.