A study was conducted between May and August 2007 to compare the intensity of human-wildlife conflicts among local communities neighbouring a fenced wildlife protected area (Lake Nakuru National Park) and an unfenced one (Maasai Mara Game Reserve) in Kenya. A self-administered, drop-and-collect questionnaire was used to collect data from 480 (n = 600, 80% response rate) and 420 (n = 600, 70% response rate) interviewees within communities on the fringes of the National Park and Game Reserve, respectively. Five problematic species were identified around Lake Nakuru National Park and nineteen around Maasai Mara Game Reserve. Major problematic species around Lake Nauru National Park included baboon, warthog and monkey while those around Maasai Mara Game Reserve included elephant, lion, zebra and wildebeest. Major complaints against wildlife included destruction of crops and property, attacking/injuring humans, preying on domestic stock, causing fear among women and children, and being a nuisance. Some wildlife problems were season and location specific. Severity of the human-wildlife conflicts (prominence and intensity of wildlife invasions) was higher within the interface area surrounding the unfenced Game Reserve than around the fenced National Park. Fencing was found to effectively control most, but not all, problematic species. Where feasible, it is recommended to form part of the overall problematic animal management strategy.