Heat shock factor 1 (HSF1) is the key protein in regulating stress response. It can be activated under heat, oxidative or another stress conditions. Dominant-positive and dominant-negative HSF1 are two types of HSF1 mutants. Both of them gain the DNA binding activity in the absence of stress. In addition, dominant-positive HSF1 acquires transcriptional activity, which dominant-negative HSF1 does not acquire. In this paper, the progress of using these HSF1 mutants in the research of cancer, neurodegenerative disorders and cardiovascular diseases will be discussed.