To detect the mutation in a given sequence, there are variety of methods developed by use of the gel electrophoresis. One of the methods, TGGE (Temperature Gradient Gel Electrophoresis), is a popular technique because it can detect mutations in DNA fragment with ease and at low cost. This study used 200 bp BamHI-digested DNA fragment containing the human $varepsilon$-globin promoter which was mutated[$varepsilon$ F1*(-141), GATA- I*(-163), and GATA-1* & $varepsilon$F1]. This BamHI-digested DNA fragment was directly used to detect the mutated DNA fragment on 50% denaturant gel with temperature gradient of 45$^{circ}C$ through $53^{circ}C$. In agreement with the theoretical result of MELTSCAN program (Brossette and Wallet, 1994) the mobilities of mutated DNA fragments were shown to be nearly distinguished on the temperature gradient gel. In contrast to the above result the heteroduplex analysis under the temperature gradient condition was shown to detect the mutated DNA fragments through the heteroduplex formation between strands of mutated DNA and wild-type DNA.