Aim of this thesis is mainly focused on subject of public procurement in Slovak republic. First chapter deals with initial description of legislative with short characteristics of relevant terms, procedures and constructive elements in the process of public purchasing and its administrative costingness. The topic of administrative costs is deeply described in next two chap-ters. Second chapter is focused on identifying theoretical concept of these costs with respect to its attributes, measurement methods, structure and origin of these costs. Analysis of subjects that have participated in survey is subject of last chapter. It is aimed at providing a rea-der with real view into problematic of Slovak Public Purchasing during year 2009 along with specification of value of administrative costs incurred in several public sector organizations and theirs relation to amount of costs that have been incurred in public purchasing and to compare these types of costs. Ending chapter serves as conclusion in accordance with observed trends and its main part drafts specific proceedings in order to improve efficiency of pub-lic purchasing and its administrative costs.