The derrick model was established based on solidworks 2013, and ansys14.5 was introduced to make the finite element analysis on the rated load and model in strong winds. The analysis indicates that all the strength and rigidity of the derrick meet the requirement of safe use under the rated load in 8th-force wind with sufficient weld strength reserve of the key parts. By comparing natural frequency of the derrick and working frequency of the drilling machine, the analysis on the main vibration mode of each modal comes to that the derrick structure of drilling machine is designed reasonably.