Nowadays, many organizations, such as companies and hospitals store and use a lot of data, that includes Personally Identifiable Information (PII).
It is mandatory to ensure the protection of PII when it is used for big data analysis. There are two kinds of protocols that can be used for this . Multiparty Private Set Intersection(MPSI) protocol and Multiparty Private Set Union(MPSU) protocol, that output the intersection and union of input sets,respectively, while preserving the sets' privacy i.e, each participant can obtain the intersection and the union of input sets without leaking other information. In our work, we propose a MPSU protocol that satisfies the important conditions for analyzing big data.