Novel multivalent polysaccharide – protein conjugate vaccine formulation. The formulation is liquid or lyophilized or a Liquid-Lyo combination pentavalent formulation of Neisseria meningitidis serogroup A, C, Y, W and X capsular polysaccharides (Men A, C, Y, W, X), each said polysaccharide being conjugated separately to tetanus toxoid (TT) carrier protein to obtain Men A, C, Y, W, X –TT conjugates, with one or more buffer and with or without an adjuvant along with pharmaceutically acceptable components/excipients.