The synthesis of one dimensional structures of nano material based sensing devices for detecting the different levels of humidity and different types gases are carried out by the template of porous anodic aluminium oxide layer. The pore morphology of anodic oxide layer depends upon the parameters (voltage level, molar concentration of electrolyte, types of electrolyte and duration of anodization) of the anodization process. The role of electric field in the growth of porous anodic oxide layer has been reported in qualitative ways by numerous authors but the calculation of electric field at each of its formation stage is missing. In this work, an analytical model for the growth of porous anodic aluminium oxide considering its each stage of formation during the anodization of aluminium sheet was developed. The origin for the development of the proposed model is based upon the facts that porous anodic oxide film is formed due to the dissolution of virtual passive layer of the substrate (alumina sheet) at the pore base in the influence of high electric field. Depending on the value of electric field at the pore base different morphology of the pore can be formed. For the development of the analytical model two cases are considered (1) nucleation of the pore (2) steady state growth of the process during the anodization process of aluminium sheet in the influence of electric field at the pore base. The develop model can be used to optimize the morphology of the anodic oxide film based sensing devices to acquire its better static and dynamic characteristics.