Peroxisome proliferator activated receptors (PPARs) belong to a subfamily of transcription nuclear factors. Three isoforms of PPARs have been identified: alpha, beta/delta and gamma, encoded by different genes and distributed in various tissues. They play important roles in metabolic processes like regulation of glucose and lipid redistribution. They also have anti-atherogenic, anti-inflammatory as well as anti-hypertensive functions. In hypertension-induced cardiac hypertrophy, both PPARa and PPARg activation reveal cardio-protective effect. Despite these beneficial functions, several recent experimental reports point to the possibille unfavorable effects of PPARs activation in lipid metabolism (lipotoxicity) in cardiomyocytes, which can lead to pathologic cardiac hypertrophy in such diseases as diabetes type 2, metabolic syndrome or obesity. This paper reviews evidences and hypotheses about the new pathophysiological aspects of PPARs activation.