We have identified a dwarf mutant line, E29, through a screen from inbred line 6421 of ethyl methanesulfonate (EMS) mutagenized population in the pepper. In this paper, E29 was studied from its phenotypes, stem and leaf morphology by means of light microscope, genetic characteristics, and also including its physiological responses to GA3, 24–eBR and IAA. The results showed that E29 and 6421 had similar phenotypes, which showed severe dwarf accompanied with wide, thick leaf blades and dark green leaves. The mutation phenotype was controlled by a single recessive gene. It was proved from the longitudinal sections of the stems that the length of mutant cell reduced, which resulted in the short stature. Transverse sections of leaf blades also revealed that mesophyll mutant cells became larger and the number of mesophyll mutant cell was more than their wild counterparts, which explained its wide and thick leaves. It was further showed that GA3 (1.0 mg/L) promoted root and hypocotyl elongation of E29, while IAA (1.0 – 4.0 mg/L) gave rise to the opposite effects, and 24–eBR(0.5–2.0 mg/L) had no effects on inhibiting or promoting root and hypocotyl elongation. Exogenous GA3, IAA or 24–eBR was failed to recover the mutant of E29 to its wild phenotype, which indicated that the dwarf phenotype was not sensitive to BR.