The innate immune system represents the first line of defense to intramammary infection (IMI) and is poised to immediately recognize and respond to the earliest stages of infection. The inherent capability of the innate immune system is mediated by its ability to recognize highly conserved motifs shared by diverse pathogens. Therefore, the objectives of this study were to determine the ultra-short spontaneous cure rates (uSCURE), the cure occurred from the immune system within 1 wk after IMI, among mastitis pathogen in the early stage of infection. Quarter milk samples were aseptically collected from all quarters of 26 lactation cows once a wk for 12-wk duration. After collection, milk samples were used for bacterial identification and the samples with positive bacterial results were chronologically sorted for determining the episodes of IMI. After starting episodes, the uSCURE were determined when the episodes was ended within 1 wk of infection by no positive bacteria was found for at least 3 following wks. Fisher’s Exact Chi-squared tests were used to determine the differences of uSCURE among mastitis pathogens. From 1,014 collected quarter milk samples, the pathogens were isolated from 455 quarters accounting for 181 IMI episodes. The episodes included 103, 6, 27, 14, 10 and 21 for coagulase-negative staphylococci (CNS), Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae, Streptococcus dysgalactiae, and other streptococci, respectively. The uSCURE of CNS (29.1%) was higher than that of Strep. uberis (3.7%) at P < 0.05 and had a tendency of higher than Strep. agalactiae (7.1%) at P < 0.15. The differences of uSCURE were not found between CNS and Staph. aureus (16.7%), Strep. dysgalactiae (10.0%) and other streptococci (19%). In conclusion, CNS has the highest rate of ultra-short spontaneous cure rate compared with other pathogens.