Objective: To explore the related factors of high-volume lymph node metastasis (HVM) in multifocality papillary thyroid carcinoma (MPTC). Methods: The clinical and pathological data of multifocality papillary thyroid carcinoma (MPTMC, d≤10 mm) and MPTC (d>10 mm) collected from Hangzhou First People's Hospital from January 2010 to March 2023 were retrospectively analyzed. Univariate and multivariate logistic regression analysis were used to analyze the relevant factors of HVM. Results: Among 566 cases of MPTMC and 381 cases of MPTC, there were 72 males and 494 females in MPTMC, 106 males and 275 females in MPTC, respectively. The median age of the patients was 47 (39, 54) and 47 (34, 56) years, respectively, and the incidence of HVM was 4.6% (26/566) and 21.5% (82/381), respectively (χ2=64.588, P<0.001). Univariate analysis showed that in patients with MPTMC and MPTC, the incidence of HVM in males was higher than that in females [15.3% (11/72) vs 3.0% (15/494) (χ2=21.487, P<0.001) in MPTMC, 33.2% (35/106) vs 17.1% (47/275) (χ2=11.492, P=0.001) in MPTC]. The age of the HVM group was lower than that of the non-HVM group [41 (33, 50) vs 48 (39, 54) years (Z=-2.128, P=0.033) in MPTMC, 38 (29, 48) vs 48 (36, 57) years (Z=-4.987, P<0.001) in MPTC]. The maximum diameter of tumors in the HVM group were higher than those in the non-HVM group [7.0 (5.0, 10.0) mm vs 6.0 (5.0, 8.0) mm (Z=-2.558, P=0.011) in MPTMC, 17.5 (13.0, 25.0) mm vs 15.0 (12.0, 20.0) mm (Z=-2.871, P=0.004) in MPTC]. Multivariate logistic regression analysis showed that larger tumor size (OR=3.027, 2.378; 95%CI: 1.287-7.117, 1.404-4.030; P=0.011, 0.001), male (OR=5.398, 1.909; 95%CI: 2.284-12.758, 1.113-3.274; P<0.001, P=0.019), and younger age (OR=3.889, 3.136; 95%CI: 1.686-8.969, 1.837-5.355; P=0.001, P<0.001) were all risk factors for the occurrence of HVM in MPTMC and MPTC. Conclusion: The proportion of HVM in MPTC patients was higher than that in MPTMC, and larger maximum diameter, male gender and younger age are related factors for HVM in MPTMC and MPTC.