Dynamic geometry software (DGS) aims to enhance mathematics education. This systematic review and meta-analysis evaluated the quasi-experimental studies on the effectiveness of DGS-based instruction in improving students' mathematical achievement. Research articles published between 1990 and 2013 were identified from major databases according to a prespecified search strategy and selection criteria. A meta-analysis was conducted based on the random-effects model to evaluate the effectiveness of DGS-based instruction in terms of standardized mean differences (SMD) of achievement test scores as outcome measures. Nine quasi-experimental DGS studies with 587 participants were eligible. The overall effect size of DGS-based instruction on achievement scores (i.e., SMD) was distinctive (SMD, 1.02; 95% CI: 0.56-1.48) compared to traditional instruction. Subgroup analysis found some groups to have better effectiveness, for example, short-term instruction with DGS significantly improved the mathematical achievement of elementary school students.