A biological decontamination gel consisting of a colloidal solution comprising from 5 to 30% by mass preferably 5 to 25% by mass still preferably 8 to 20% by mass based on the mass of the gel of at least one inorganic viscosifying agent: 0.5 to 10 mol/L of gel preferably 1 to 10 mol/L of gel of at least one active biological decontamination agent 0.05 to 5% by mass preferably 0.05 to 2% by mass based on the mass of the gel of at least one super absorbent polymer 0.1 to 2% by mass based on the mass of the gel of at least one surfactant and the remainder of solvent. A biological decontamination method applying this gel.
