Abstract: OBJECTIVE To investigate the effect of diagnostic value of blood routine indicators in children with acute febrile with no obvious focus of infection, so as to provide a theoretical basis for clinical diagnosis and treatment. METHODS A total of 128 patients with acute fever treated in the hospital from Oct. 2014 to Sept. 2015 were selected as research subjects, who were given a blood routine test, according to the clinical final diagnosis to analyze the clinical significance of routine examination indicators. RESULTS The peripheral blood white cells counts of children in various severe diseases were compared and the difference had no significace. The levels of C-reactive protein and the procalcitonin concentration in severe disease children were significantly higher than those in non-severe disease children. The peripheral blood white cells counts were under comparison, which had no significant difference between the children with bacterial infection and mycoplasma infections, but there was significant difference between children with mycoplasma infections and virus infection(P<0.05). CONCLUSION The C-reactive protein and the procalcitonin could provide reference for the etiology diagnosis and disease severity judgments for children with acute fever but no obvious focus of infection, which improves the diagnostic accuracy.