The invention discloses fermented sour soup flavored beef jerky and a preparation method thereof. The beef jerky comprises, by weight, 90-110 parts of beef, 1.8-2.2 parts of green tea, 0.4-0.6 part ofginger slice, 1.8-2.2 parts of rock sugar, 0.2-0.4 part of compound phosphate, 2.0-2.4 parts of lactic acid bacteria and yeast, 1.3-1.7 parts of glucose, 0.8-1.2 parts of salt, 5.5-6.5 parts of honey, 0.3-0.7 of chili powder, 0.8-1.2 parts of spiced powder, 0.8-1.2 parts of pepper, 0.8-1.2 parts of Sichuan pepper, 0.8-1.2 parts of Sichuan pepper powder, 7.5-8.5 parts of red sour soup and 5.5-6.5parts of sesame oil. The sour soup flavored beef jerky prepared by the above components has the unique flavor of the sour soup, the flavor of the beef jerky is more excellent, the nutritional value ishigher, the digestibility of the fermented beef jerky is improved, and the flavor is improved. The probiotics in the fermented beef jerky inhibits the growth of harmful microorganisms, prolongs the shelf life of the beef jerky, and improves the safety of the beef jerky.