The aim of the article is to reflect the necessity of introducing objective criteria in articulating monetary value of the damages caused to archaeological sites (immovable cultural monuments) in a result of illegal activities. The research focuses on the assessment criteria for damages and resulting diminishment of economic value that are being used in several countries and examines key interests and stakeholders in damage assessment process and outcome. It further describes the corresponding situation in Latvia, determines the existing challenges and proposes basis for improvement in administrative and legal procedures. Methods applied in the research are literature review, legal framework and documentary analysis, statistical analysis and elements of qualitative content analysis. International intercomparisons have been made consulting with foreign experts. The assay is mostly done from legal and socio-economic point of view. The results of the research could be used for the purposes of amending legal regulation and damage assessment mechanisms.