Objectives To compare the clinical outcomes of isolated anterior cruciate ligament (ACL) reconstruction with combined reconstruction of the ACL and anterolateral ligament (ALL) of the knee. Methods A search was conducted on the PubMed, Medline, Google Scholar, EMBASE, and Cochrane library databases, in line with the PRISMA protocol. The indexation terms used were “anterior cruciate ligament” OR “acl” AND “anterolateral ligament” AND “reconstruction.” Articles that compared patients submitted to combined ACL and ALL reconstruction with those submitted to isolated reconstruction of the ACL, with levels of evidence I, II, and III, were included. Studies with follow-up of less than 2 years and articles that did not use “anatomical” techniques for ALL reconstruction, such as extraarticular tenodesis, were excluded. A meta-analysis with R software was conducted, with a random effects model, presented as risk ratio (RR) or mean difference (MD), with a 95% confidence level (CI) and statistically significant at p < 0.05. Results Ten articles were selected, with a total of 1495 patients, most of whom were men, of whom 674 submitted to ACL and ALL reconstruction and 821 to isolated ACL reconstruction. Combined ACL and ALL reconstruction exhibited a statistically significant advantage in residual pivot shift (RR 0.34, 95% CI 0.24–0.47, I2 = 0%, p < 0.01), rerupture rate (RR 0.34, 95% CI 0.19–0.62, I2 = 0%, p < 0.01), Lachman test (RR 0.59, 95% CI 0.40–0.86, I2 = 21%, p < 0.01), and postoperative Lysholm score (MD 2.28, CI 95% 0.75–3.81, I2 = 73%, p < 0.01). Conclusions Combined ACL and ALL reconstruction obtained better postoperative clinical outcomes when compared with isolated ACL reconstruction, especially in reducing residual pivot shift and rerupture rate.