The main aim of this research was to study the epizoological situation and to determine the most effective antiparasitic drugs used for the treatment of Toxoxariasis in dogs. The objectives of the investigation were: to determine the level of the spread of Toxocariasisi in dog in accordance with their age, sex and the seasons of the year; to examine the level of contamination of the soil with the eggs of T.canis; to identity the most effective medications for treating Toxoascaris. The investigation has shown that Toxocariasis, is widely spread in the young dogs. The level of extensive invasion in young dogs 2 to 4 months old is 100% and the intensive invasion is 18,5 eggs on a microscopic level. It was detected the similar tendency of the contamination with Toxocariasis in the young dogs that are 6 to 12 months old. The level of extensive invasions is 100%, but the intensive invasion is only 9,6 eggs. The level of extensive invasion of Toxocariasis in the young dogs from 1 to 3 years old decreases to 62%. The lowest level is in the young dogs which are 1 year old. The intensive invasion is 5,8 eggs. According to the season, the highest level of infestation with Toxocariasis is in summer. The male dogs are more susceptible to the invasions of Toxocariasis than female. The physical environment and the dogs’ utensils are great sources of infestation with eggs. Pratel- 95,5%, Alben C- 93,75, Pyrantel- ssuspense- 90,8% , are anthelmintic drugs with the highest efficacy, but Azinox-plus has a lower therapeutic effect.