Outsourced Database Security - Efficient sequencing methods produce a large amount of genetic data, and make it accessible to researchers. This leads genomics to be considered a legitimate big data field. Hence, outsourcing data to the cloud is necessary as the genomic dataset is large. Data owners encrypt sensitive data before outsourcing to maintain data confidentiality and outsourcing aids data owners in resolving the issue of local storage management. Because genomic data is so enormous, safely and effectively performing researchers’ queries is challenging. In this paper, we propose a method, PRESSGenDB, for securely performing string and substring searches on the encrypted genomic sequences dataset. We leverage searchable symmetric encryption (SSE) and design a new method to handle these queries. In comparison to the state-of-the-art methods, PRESSGenDB supports various types of queries over genomic sequences such as string search and substring searches with and without a given requested start position. Moreover, it supports strings of alphabets as sequences rather than just a binary sequence of 0, 1s. It can search for substrings (patterns) over a whole dataset of genomic sequences rather than just one sequence. Furthermore, by comparing PRESSGenDB’s search complexity analytically with the state-ofthe-art, we show that it outperforms the recent efficient works.