The based on crgA, and sacD, siaDb, c targets was design for Multiplex-PCR2 to detection for N meningitidis và serogroupA, B, C in single-tube assay, its sensitivity for the four targets detection of 104 cfu / ml - 105 cfu / ml concentration and the specificity of assay was 100% và 100%, 94, 11%, 87, 5%.