THIS research assessed the concentrations of tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ) and interleukin-6 (IL-6) in Nigerian indigenous dogs (NID) experimentally infected with Trypanosoma congolense (T. congolense) and correlated with some haematological and biochemical indices.  Fifteen NID of weight (9.3±1.04 kg) were randomly assigned into three groups of five each. Group A was uninfected and untreated. Group B received T. congolense (2.5 x 105), but untreated. Group C received T. congolense (2.5 x 105) and treated with diminazene aceturate on day 17 post-infection (pi). Blood was obtained pre-infection, pi and post-treatment (pt) for cytokines assessment using ELISA. Serum TNF-α increased significantly (p < 0.05) in groups B and C on days 10 and 17 pi but decreased on day 5 pt in group C compared to groups A and B.  Serum IL-6 increased significantly in groups B and C on days 1 to 22 pi. Both TNF-α and IL-6 correlated positively with monocytes count, creatinine, and urea.  Serum TNF-α correlated negatively with PCV, erythrocytes count, haemoglobin concentration (Hb) and albumin, while IL-6 correlated negatively with on PCV, Hb and albumin. In conclusion, IL-6 was elevated post infection and remained elevated post treatment. Tumour necrosis factor - alpha concentration was elevated in NID infected with T. congolense, but decreased significantly post treatment. Both IL-6 and TNF-α positively or negatively associated with assessed haematological and biochemical indices. In conclusion, proinflammatory cytokines are elevated in NID experimentally infected with T. congolense and caused some pathology.