Objective To investigate the effects of photodynamic reaction on cytokines production of HaCat keratinocytes treated with 5-aminolevulinic acid (ALA). Methods The HaCat cells were cocultured in vitro with different concentrations of ALA. Three hours later PpIX levels in HaCat cells were detected, and phtotodynamic reaction was induced by 632.8 nm laser radiation on cells. The cell death was analyzed using a flow cytometer to evaluate reactive intensity. The cytokines contents in supernatant were determined, including interleukin (IL)- lα, IL-6, basic fibroblast growth factor (bFGF), endothelin (ET)-1 and tumor necrosis factor (TNF)-α. Results Different cellular PpIX levels and cell death rates were seen according to ALA concentrations. The cell death rate did not exceed 10% and showed a positive linear relationship with ALA concentration (P＜0.05), when the later was at 0.0-1.6 mmol/L interval. The levels of IL-1α, bFGF and TNF-α increased as ALA concentration ascended at this interval (P＜0.05). No significant correlation was found between ALA concentration and IL-6 or ET-1 level (P＞0.05). Conclusion The photodynamic reactive intensity could be enhanced by increasing ALA concentration. And at certain scope, higher reactive grade might induce higher levels of keratinocyte-derived cytokines.