PBM Gelora Perkasa Belawan is a loading and unloading company that plays a strategic role in maintaining the smooth distribution of goods at the port through the management of metal box cargo. This study aims to analyze the effect of the metal box loading process on the smoothness of loading and unloading activities, as well as to identify its supporting and inhibiting factors. The research method used is a descriptive method with a quantitative approach. Data collection was carried out through field observations for six months, in-depth interviews with operational personnel, documentation, and literature studies. The results showed that the metal box loading process significantly affects the smoothness of loading and unloading operations. Carrying out loading in accordance with Standard Operating Procedures (SOP)—supported by the readiness of equipment such as cranes, slings, spreaders, forklifts, and truck trailers, as well as complete supporting documents such as the Stowage Plan and Hatch List—can increase efficiency and the overall smoothness of the process at the port. Conversely, technical constraints such as lifting equipment damage, truck delays, bad weather conditions, and a lack of communication between officers can hinder time efficiency and risk damaging cargo as well as disrupting ship stability. Therefore, optimization strategies such as routine inspection of cargo and equipment conditions before operation, precise positioning of cargo according to the stowage plan, and improved coordination among field officers are key steps to minimize the risk of obstacles. Overall, a well-planned and well-supervised metal box loading process ensures that loading and unloading activities run more smoothly, safely, orderly, and on time at PT. PBM Gelora Perkasa Belawan.