Pollution of insulator surface could lead to a flashover of insulators, The flashover of insulators caused by pollution generally dominates at voltages above 500 KV. Mechankm of pollution flashover is veiy complex as it depends on numerous factors. Over the years the researchers have presented vanous models for better understanding of flashover phenomenon and prediction of fiashover voltages. Due to complexity of problem researchers made various assumptions to simp1i.Qthe problem. The objective of this dissertation is to review and compare various models and to evaluate their capabilities in predictingthe flashovervoltages of insulators. Severai models have been reviewed and out of these models, those which contain sufficient information for predicting the flashover voltages have been selected. The selected models have been applied to different types of insulators and the flashover voltages are calculated. In order to compare the models the conditions e.g. resistivity, under which the mode1 are applied to insulators are kept the same. Five types of configurationsof insulator models are considered, i) 10 x 1 cm fiat plate, ii)10 x 10 cm flat plate, üi) cylinder, 100 cm long and 15 cm diameter, iv) IEEE?nsulator and v) Anti-Fog insulator. The calculated flashover voltages and other results are wmpared with each other and with experimental results. The author wishes to express his sincere gratitude to his advisor Dr. M- R Raghuveer for his encouragemenf guidance and vaiuable discussions during the course this work The author expresses his thanks to his employer Pauwels Canada for their support for this work. Finally, the author expresses his utmost appreciation to his wife Kaushal and children Himanshu and Sonal for their understanding*encouragement and bearing with me during the petiod of this work 2.3. 1.2.Amode1 of Aston.