The invention discloses a strain of caries resistant lactobacillus plantarum K41 and application thereof. Lactobacillus plantarum K41 provided by the invention is preserved in Common Microorganism Center of Chinese Microorganism Strain Preservation Management Committee, with preservation number of CGMCC No.15462, and preservation date of March 20, 2018. The strain is separated from farmyard self-made pickles in Yanan Road, Shunqing District, Nanchong, Sichuan, grows well on an MRS agar culture medium, can inhibit growth of streptococcus mutans UA159, forming of exopolysaccharide, degradation of hydroxyapatite, and forming of a biological film, has good auto-agglutination and copolymerization capability, is good in tolerance for antibiotics, salt and acid, and is easy to be planted in the oral cavity. Animal experiment shows that K41 can inhibit rat enamel demineralization and caries degree, can be applied to functional food, and has very important meaning for body health.