This study aims to develop a new evaluation technique for Northern Corn Leaf Blight (NCLB) resistance in maize under greenhouse condition. Ki48/Ki47 F2 (160 lines) and 2 commercial verities (Hi-Brix3 and Insee2) were evaluated. For this technique 10-14 day old seedlings (4-5 leaves) were sprayed with ACIL1 spore suspension (104spores/ml.) for infection. The results of this technique correlated with the results from the common technique under field condition which used 21-25 days old seedlings (6-7 leaves) (correlation value = 0.658). This evaluation technique was used to assist in QTL mapping of NCLB resistance. Population of Ki48/Ki47 F2 (160 lines) were analyzed for QTL mapping by using Simple Sequence Repeats (SSR) markers. It was found that major parental polymorphism located on chromosome 5 and chromosome 8. When Single QTL analysis was performed SSR marker UMC1365 could clearly indentified qualitative trait loci on chromosome 5 and SSR markers UMC1095 UMC1268 and UMC2356 could clearly indentified qualitative trait loci on chromosome 8.