In the article is examined the problem of correlation between authority and opposition in transitional society. The political authority is the main factor of construction and consolidation of political system. The political opposition is the necessary element of the democratic political system.It is the efficient instrument of contradiction`s civilized solution between the interests of big groups of people who are reprezented by the political parties. The opposition is an integral part of "checks and balances" system, on the basis of which the political system functions. The authors consider that opposition in western democracies fulfils the function of relaxation of social tension, also is themeasure to avoid the social conflicts and crisis situation. In the article the great attention is paid to parlamentary opposition. Unlike the other types of opposition parlamentary opposition is the only type which belongs to a system of political authority. The authors examine the differences between authority and opposition in the Republic of Moldova. The political crises which appear in society need the new forms of dialogue with opposition. In spite of the fact that ruling and oppositional parties compete between them in political process, they have to achieve the consensus on the basic problems. The political situation in society, the stability of political system depends on the constractive dialogue between authority and opposition.