Background: Patients with hepatocellular carcinoma (HCC) and microvascular invasion (MVI) are susceptible to early recurrence (ER) after hepatectomy. The use of postoperative adjuvant transcatheter arterial chemoembolization (TACE) for patients with HCC and MVI remains a subject of debate. Methods: A total of 1,191 patients with HCC and MVI from 16 participating centers were retrospectively analyzed. A nomogram for predicting ER was developed using risk factors via multivariate logistic regression in the training cohort, with performance validated in the internal and external validation cohorts. Patients were categorized into high- and low-risk groups based on maximum Jordon index, which was used to continue exploring the long-term prognosis and the impact of adjuvant TACE therapy. Results: In total, 217 (43.1%), 115 (45.6%), and 189 (43.4%) patients with ER were found in the training, internal validation and external validation cohort, respectively. The DCDAM score, which incorporates diameter, cirrhosis, differentiation, alpha-fetoprotein (AFP), and MVI grade, demonstrated superior net benefit and accuracy in predicting ER compared to traditional models across three cohorts. The high-risk group (DCDAM score >169) had higher cumulative recurrence rates and worse overall survival (OS) (median OS: 22.0 vs. 38.3, 17.5 vs. 41.7, and 23.6 vs. 45.2 months, all P<0.001) compared to the low-risk group (DCDAM score <= 169) in all cohorts. TACE-adjuvant therapy improved OS in the high-risk group but not in the low-risk group. Conclusions: DCDAM score achieved an optimal postoperative prediction of ER among patients with HCC and MVI. This model can help screen subjects who can benefit more from postoperative adjuvant TACE.