The purpose of this paper is to design and analyse a two stage speed reduction gearbox housing. There has been hardly any rigorous design procedure adopted for gearbox housing during the design of a gearbox. This has led to a large number of failures in such systems and hence the need for a definite design procedure has risen. The gear train and the shafts were designed in accordance with standard design data. The gear train is theoretically mounted in a cuboidal box termed as the housing. The torsional critical speed of the rotor system and the lateral critical speeds of the shafts were obtained using ANSYS. A finite element modelling of the gearbox housing was carried out in ANSYS and the same was analysed to obtain its natural frequency and stress distribution. All the ANSYS solutions were extensively evaluated with different theoretical methods such as the Raleigh's energy method and were found to be consistent. A comparison of the natural frequency of the housing, the torsional critical speed of rotor system and the lateral critical speeds of each of the shafts with the exciting frequency clearly showed the former were far above the exciting frequency hence qualifying the gear box housing. A few industrial practices were taken up as case studies to understand their implications on the safety of the gearbox. The degree to which the gearbox stability is forfeit due to the changes made in each of the three case studies is compared. The complete analysis concluded that the housing design plays a very significant role in the industrial scenario.