SUMMARY
The aim of this study is investigating the effect of pricing system changes on financial performance with emphasis on environmental uncertainty. Sample of study are all accepted companies in the Stock Exchange of Tehran in 2014. Results showed that changes in the pricing system have a negative impact on corporate financial performance. So, it is recommended to the managers and owners of companies, for enhancing and improving the financial performance of company, to use a stable and sustainable pricing system, and along with economical and environmental changes, to have little changes. When the environmental uncertainty is higher, the effect of changes and pricing systems will be more. So it is suggested to managers and other consumers when environmental uncertainty is high, they should consider negative effects of pricing system on corporate financial performance.