The field of public procurement is one of the most vulnerable to corruption, and ensuring the integrity of subjects involved in public procurement constitutes a current approach to corruption prevention and research. Strengthening the integrity of public procurement subjects is an essential measure to prevent corruption, because public procurement is one of the key areas in which the public sector and the private sector interact financially. However, this interaction is based on public money, which attracts the corrupt subjects to illegal activities, due to the position they hold, they take advantage of public funds in personal interest or of a group at the expense of the general interest. Specifically, this paper researches the general conceptions of public procurement and integrity, the national normative framework regarding integrity in public procurement, identifies and analyzes the categories of subjects, their role, the causes and consequences of non-compliance with integrity in the public procurement system. In conclusion, it is deduced that the lack of integrity of subjects in the public procurement system generates not only deficient policies, norms and procedures, but endangers public respect for the government, erodes the rule of law, distorts the economy of a country and seriously affects the fundamental rights of citizens.