This paper introduces a Resource Description Framework (RDF)-based ontology to model Personal Identifiable Information (PII). The triples construct is applied to 'atomic' private statements. RDF is divided into two modes: personal information mode (PIRDF) and non-personal information mode. PIRDF is a restrictive version of RDF where its constructs follow the triple format so that the semantic subject of the atomic private statement coincides with the subject of the RDF triple. Related (compound) pieces of personal information are also made in an RDF-independent collection to preserve their relationship. Literals are not allowed to embed personal information. These restrictions do not introduce any change in the syntax of RDF. Privacy protection mechanisms can be constructed upon PIRDF.