Objective: To provide a new basis for the detection of the central nervous system infection cases, we explored and compared the role of cerebrospinal-fluid (CSF), matrix metalloproteinases 9 (MMP-9) and interleukin 1 (the level of IL -1 β) in the central nervous system (CNS). Methods: Sixty cases of children acute central nervous system infection were selected, including 30 cases of viral encephalitis children (VE) and 30 cases of purulent meningitis children (PM). Forty cases of non-central nervous system infection children were control group. The serum albumin (SA1b) of each group was detected by full-automatic analysis instrument, and the CSF albumin (CA1b) was detected by immunoephelometry and the albumin index (AQ) was accounted. ELISE was used to detect the levels of MMP-9 and IL-1 β in serum and cerebrospinal-fluid. Results: The level of MMP-9 in the serum of groups of VE, PM and control were (267.84 ± 91.88) μg/L, (488.98 ± 159.07) μg/L and (133.04 ± 31.68) μg/L, while in the CSF were (37.18 ± 17.78) μg/L, (117.9 ± 42.87) μg/L and (10.36 ± 5.43) μg/L; The level of IL-1 β in serum of groups of PM, VE and control were (19.69 ± 11.12) ng/L, (24.37 ± 4.13) ng/L and (15.01 ± 3.89) ng/L, while in the CSF were (66.94 ± 10.65) ng/L, (106.27 ± 12.79) ng/L and (49.98 ± 12.59) ng/L; The level of CAlb were (0.53 ± 0.15) g/L, (1.05 ± 0.27) g/L and (0.17 ± 0.07) g/L and AQ were (13.75 ± 3.44), (26.99 ± 7.28) and (4.63 ± 2.04). The PM, VE were respectively compared with the control, the levels of IL-1 β and MMP-9 in serum and CSF all increased, with statistically significant difference.The VE, compared to the PM, the level of IL-1 β in serum and CSF all decreased, with statistically significant difference; The level of MMP-9 in serum and CSF all decreased, with statistically significant difference. The level of CA1b and AQ in the VE and PM all increased, with a statistically significant difference. The level of MMP-9 and IL-1 β in serum and CSF of the PM and VE were positive correlation relationship. Conclusion: The increasing of the levels of IL-1 β and MMP-9 in serum and CSF, and the increasing of AQ in children with central nervous system infection indicate that MMP-9 and IL-1 β may play a role in the pathophysiologic course of blood-brain barrier impairment in the central nervous system infection.