Objective：To observe the changes in platelet（PLT） count，mean platelet volume（MPV） and platelet distribution width （PDW） in patients with severe burn and to explore their influencing factors. Methods：Changes of PLT count，MPV，and PDW were de－termined in 65 patients with severe burn. The relationship between these parameters and degree of burn was analyzed by single-factor analysis. The possible inducing factors of PLT count changes（total burned area，Ⅲ degree burn area，acceptance of component trans－fusion，cutting the scab area，using growth hormone，etc） were detected. Logistic regression was used to analyze the factor causing PLT count back to normal. Results：①The value of PLT count measured at 24 h after the burn was much higher in healthy control group than in the other two groups（P<0.05） while the values of MPV and PDW were much lower in healthy control group than in the other two groups（P<0.05）. There were significant differences in PLT count，MPV，and PDW between severe burn group and moderate burn group（P<0.05）. ②The results of Logistic regression analysis showed that total burned area and intravenous drip of Ulinastatin were factors that cause PLT count back to normal after the treatment. Conclusions：There are obvious changes in the values of PLT count，PDW，and MPV of patients with severe burn at 24 h post burn. Positive and effective treatment can reverse the condition.