The Pangasinan State University established the Open University Systems in the latter part of the year 1996. It was formally launched at PSU-Lingayen in March 1997 with the presence of former Speaker Jose C. De Venecia who was instrumental in the funding of the initial two years of operation of the system. The establishment of the PSU-OUS was borne out of the need to respond to the unique needs for further professional and technical development of career people, administrators and managers, technicians and workers who may not have the time or opportunity to attend or perform the regular university programs while at work.

The PSU-OUS began with Diploma Courses in the graduate level and computer technology courses in the undergraduate level. Most of the Diploma Courses are in collaboration or partnership with international or national government and private organizations. All of these programs are accreditable to the corresponding degrees and levels. Partnership with participating agencies are covered by Memoranda of Agreement for sharing of resources and expertise.

As of this writing, the PSU-OUS has now expanded geographically to include Ilocos Norte in the North and Leyte in the South. As far as the fields of clientele are concerned, the PSU-OUS has expanded its services to agriculture, fishery, education, management, and technology. Specifically, the PSU-OUS has or is now serving the needs of the Department of Agriculture and the Agricultural Training Institute or DA-ATI through the SPREAD (Scholarship Program for the Revitalization of Extension System of the Agriculture Department), the Department of Education, Culture and Sports or DECS in the Learning for Effective Administrator Development or LEAD and the Special Program for Educational Evaluation and Development or SPEED, the Palompon Institute of Technology or PIT through the Special Certificate for Academic Leadership Effectiveness or SCALE, the National Power Corporation or NPC in the Executive Course for Excellent Leadership or EXCEL, the Philippine National Police through the Basic and Advance Leadership Programs, the Department of Interior and Local Governments or DILG, and various professional groups and youths.