The invention provides an energy-saving and environment-friendly synthesis technology for 1,2,4-1H triazole. The technology comprises following steps: S1, a formamide raw material is totally put in areaction kettle in advance, hydrazine hydrate is slowly added to formamide from an elevated tank, and a main product 1,2,4-1H triazole is produced through reaction; S2, ammonia produced in S1 enters an acid spraying device through a gas phase inlet, formic acid enters the acid spraying device through an acid inlet, and cooled ammonia and sprayed formic acid react to produce ammonium formate; S3, ammonium formate produced in S2 is cooled in the acid spraying device, flows back to the reaction kettle and reacts with hydrazine hydrate, and the main product 1,2,4-1H triazole is produced. Accordingto the energy-saving and environment-friendly synthesis technology for 1,2,4-1H triazole, formic acid is added to the acid spraying device, so that firstly, production of ammonia as a byproduct is reduced, secondly, the byproduct ammonia is used sufficiently, consumption of formamide is reduced, the use is convenient, and the raw materials are saved.