Paclitaxel remains the first-line chemotherapy regimen for many malignant tumors. However, prognosis and adverse events under different dosing regimens (one-week versus three-week treatment) remain contradictory in many randomized controlled trials (RCTs). Here, we performed a comprehensive meta-analysis to measure the efficacy and toxicities of these two dosing regimens. Four databases were systematically retrieved. RCTs comparing two paclitaxel dosing regimens for advanced malignant tumors with assessable outcomes (e.g., overall survival (OS), progression-free survival (PFS), toxicities, response rates) were included. In total, 19 eligible RCTs involving 9 674 patients were included. Meta-analysis of pan-cancers revealed that weekly paclitaxel treatment was more beneficial regarding PFS compared to three-week paclitaxel treatment (hazard ratio (HR) = 0.90, 95% confidence interval (CI) = 0.82-0.99, P = 0.02). Nevertheless, there was no significant difference in terms of OS between the two dosing regimens (HR = 0.98, 95%CI = 0.91-1.06, P = 0.62) or other tested subgroups. In terms of serious adverse events, grade 3 or 4 (G3/4) neutropenia, G3/4 febrile neutropenia, G3/4 arthritis, and G3/4 alopecia occurred less often under weekly paclitaxel treatment. In summary, Weekly paclitaxel treatment demonstrates better PFS and fewer chemotherapy-induced hematological and non-hematological toxicities compared to the three-week paclitaxel regimen.