Most environmental goods belong to non-market resources.They have no market prices and therefore,are undervalued or ignored by its values in nowadays' market system.This is the basic root of global environment issue.Although some non-market value elicitation techniques such as revealed preference(RP) and stated preference(SP) have been pervasively used in environmental economics to estimate environmental values,these techniques are still falling into value monistic neoclassical economics and ignoring the value plurality,incommensurability and incomparability.The lexicographic preference could describe the plural environmental values and reflect the ethical,public,and political features of environmental goods.Comparing to welfare maximization and compensation in neo-liberal economics,deliberation is a preferable mechanism that could discover and accommodate environmental plural values,and it is also the mechanism resolving the value conflicts in today's civil society.