Korea experienced a recession in the shipbuilding industry due to a decline in orders for vessels and a lack of orders from the Korean market. In 2017, the amount of orders has increased compared to the previous year, but it is expected to be only 60% of the previous level in 2020. However, it will be 20 years from 2003, when shipbuilding orders have increased substantially in 2023. In this paper, the stress distribution and safety factor of Offshore Lattice Boom Crane mounted on offshore plant is confirmed in accordance with the luffing boom angle and critical load. The possibility of buckling is checked through buckling factor. In addition, OLBC was designed and evaluated based on API and ABS standards for offshore plants.