Introduction: Gingival bleeding is one of the cardinal signs of inflammatory gum disease which if untreated can lead to periodontal disease and eventual tooth loss. This study assessed the knowledge and clinical presentation of inflammatory gum disease among Nigerians in the South-South geopolitical zone. Methods: Self-administered questionnaires were filled by all consenting patients that attended the Oral Diagnosis Clinic of the University of Port Harcourt Teaching Hospital between May and July 2017. Information elicited were socio-demographics, knowledge on causes and sequelae of gingival bleeding. Indices used were Gingival Index (GI), Sulcular Bleeding Index (SBI) and Simplified Oral Hygiene Index (OHI-S). Data was analyzed using epi-info and level of significance was set at <0.05. Results: 308 participants were recruited with M: F ratio of 1:1.3 and mean age of 34.2(±13.4) years. Two-fifth (42.1%) had gingival bleeding while brushing. Though 51 (36.4%) knew gingival bleeding is abnormal, more than half [35(59.3%)] did not know what caused their bleeding. Some reasons given for gingival bleeding while brushing were dental infection [10 (17.0%)] and hard bristled toothbrushes [98 (13.6%)]. Majority [234(70%)] didn’t know the sequelae of untreated gingival bleeding. Clinical examination showed 76(24.7%) had halitosis, 101(32.8%) bled on probing. 131(42.5%) had a gingival index of 2. Mean MGBI and OHI-S were 1.16(±0.9) and 1.74(±0.9) respectively. 33(10.7%) participants had poor oral hygiene. Conclusion: The participants had a poor knowledge of inflammatory gum diseases. There is the need to increase awareness among the populace and encourage prompt treatment thereby reducing its avoidable sequelae like tooth loss.