The invention discloses a method for rapidly detecting content of ammonia and acetylene mixed gas. The method utilizes common cheap chemical reagent diluted acid, bromine saturated solution of potassium bromide, a hydrogen sulfide detection pipe and a hydrogen phosphide detection pipe, uses a simple syringe and fulfills the aim of rapidly and accurately detecting the ammonia and acetylene mixed gas. Conventionally, a gas chromatographic method is adopted to carry out detection, a sample contains ammonia and thus generates large damage to a gas chromatograph and a chromatographic column, the sample is poor in detection reproducibility and long in detection period, and real-time monitoring on production cannot be implemented. According to the invention, content of the ammonia is obtained onthe basis of a case that the ammonia is very easy to react with acid; the sample in which the ammonia is absorbed mainly contains acetylene, content of the acetylene is rapidly detected by adopting abromine method, non-condensable gas is calculated by a decrement method, and content of hydrogen sulfide and hydrogen phosphide is detected by the corresponding detection pipes. The detection method has the advantages of simple instrument and equipment, simplicity and rapidness for operation, high sensitivity, cheapness of the reagent, easiness for obtaining the reagent and saving of a great amount of economic and time cost, and is popularized and applied in production.