Abstract Maritime transportation is important to national development because of Taiwan is in surrounding seas region. Therefore it is necessary that this research aimed to safety of the crane transportation system. This research investigated davit structure with a telescopic arm of a ship by means of the static analysis and modal analysis. To achieve the purpose, the researcher used the computer-aided design software Solidworks to set up this structure model. After that, he used finite element analysis software ANSYS to analyze the data. This research simulated in three situations. In static analysis, the researcher found the maximum displacement, the maximum von Mises stress and factors for safety of the structure in 16 dimensional sets in 53¢X of inclination at the davit with the telescopic arm being the shortest. After that, he discussed its tendency situation. In addition, he also checked the original structure in 53¢X of inclination at the davit with the telescopic arm being the longest and horizontal at the davit with the telescopic arm being the longest, respectively. In modal analysis, the researcher found natural frequencies and vibration shapes of the original structure. The structure had good vibration-proof ability and the resonance effect possibility not to be high. Generally, the researcher hoped that this study could provide helpful references for the relevant davit structure designers in the future.