Gastrointestinal parasites are either worms or one-celled animals that inhabit or populate the intestinal tract thereby causing gastroenteritis. The book is geared towards unraveling the prevalence of gastrointestinal parasites among 104 dog's residents in four communities (Palm Street, Atakpa street, Anantigha, and Atamunu) in Calabar South Local Government Araea of Cross River state, Nigeria by using microscopy techniques. The result showed that out of 104 dogs 73 dogs (70.19 %) were positive for gastrointestinal parasites. The result revealed high presence of gastrointestinal parasites as follows: Toxocaracanis (41%), Ancylostoma caninum (4%), Trichuris vulpis(17%), Dipylidium caninum (17%), and Cystoisospora(14%). Also, male dogs were less infected (42.47%) than female dogs (57.53%). The prevalence of infection by gender and community was statistically significant (p < 0.05). Hence, this study succeeded in unraveling a high endemicity of gastrointestinal parasite infection among dogs in four communities (Palm Street, Atakpa Street, Anantigha, and Atamunu) in Calabar South Local Government Araea of Cross River state, Nigeria.