A watergel explosive is a fuel sensitized explosive mixture consisting of an aqueous ammonium nitrate solution that acts as the oxidizer. Watergels that are cap-insensitive are not strictly explosives and are referred to as blasting agents. Water gel explosives have a jelly-like consistency and come in sausage-like packing stapled shut on both sides and as a bulk explosive.

Water gels usually have many different ingredients. They contain a gelatinizing agent, also known as a thickener, that modifies their consistency, ranging from easily pourable gels to hard solids. Polyvinyl alcohol, guar gum, dextran gums, and urea-formaldehyde resins are the typical gelling agents. Guar, specifically, is a gelling agent used for the aqueous portion of the water gel explosives. The primary component of water gels is monomethylamine nitrate. Monomethylamine nitrate is made of methyl methacrylate or MMA, formaldehyde and ammonium nitrate. Watergel explosives are also made of ammonium nitrate, calcium nitrate, aluminum, ethylene glycol and TNT. The proportions of these components vary depending on the desired explosiveness of the watergel.

Watergels are generally more energetic and more expensive than equivalent emulsion type explosives.

In Australia watergels are supplied by MAXAM explosives.