Northern leaf blight (NLB) caused by the fungus Setosphaeria turcica is an important foliar disease of maize (Zea mays L). The intermated B73 × Mo17 (IBM ) recombinant inbred lines were used to fine map QTLs for resistance to NLB. A total of 248 RILs were evaluated at Aurora NY in summer 2006. Traits assessed were the female and male flowering dates, the anthesis-silking interval (ASI), the incubation period, the diseased leaf area on two dates prior to flowering, the disease severity on four dates post-flowering, and the area under the disease progress curve (AUDPC). QTLs were detected for each trait by composite interval mapping with R² ranging from 3% to 13%. Disease resistance QTLs in bins 2.02, 3.05, 6.05, 9.02, and 9.04 were found overlapped for most traits in the primary infection (incubation period and pre-flowering diseased leaf area), and disease QTLs detected in bins 1.02, 1.06, 2.02, 3.05, 3.09, 4.06, 4.08, 5.00, 8.01, 8.05, and 9.07 were overlapped for most traits in the secondary infection (disease severity ratings and AUDPC), suggesting they were important for these stages, respectively. Disease QTLs identified were contributed from both the more resistant parent Mo17 and the more susceptible parent B73. Evidence from previous studies supported disease QTLs found in bins 1.06, 3.05, 4.06, 6.05, and 8.05, which coincided with bins identified in the present study, suggesting these regions might be generally important for NLB resistance. There was no significant evidence for correlation between plant maturity and disease resistance in this study; however, correlations between ASI and disease traits were detected. QTLs for ASI in bins 1.02, 2.02, and 9.02 were also found to overlap with disease resistance QTLs. This suggests that tolerance to environmental stresses and resistance to diseases may be correlated, due to pleiotropy or linkage.