John W. Gates of New York City, one of the founders of Texaco, established Port Arthur Business College in 1909, to train people for the petrochemical industry, then in its infancy. The college became Port Arthur Collegiate Institute in 1911, when the school was presented to the Board of Education of the Methodist Episcopal Church North, a forerunner of the present United Methodist Temple. The church operated the growing campus until 1918, when it was turned over to a non-profit Texas corporation. This corporation had no capital stock and was overseen by a self-perpetuating board of trustees. The name of the school was changed back to Port Arthur Business College and finally, in 1932, to Port Arthur College.

On July 31, 1974, another milestone in the school's history was reached. W. Sam Monroe, then President of Port Arthur College and a Lamar University regent, presented his fellow members of the Lamar board a resolution seeking merger of Port Arthur College into Lamar University. The 21 trustees of the school agreed that the merger would be in the best interests of both institutions and their constituencies.

The 64th Legislature of the State of Texas authorized the merger and appropriated $600,000 for creation of the Lamar University Center at Port Arthur. On Aug. 21, 1975, the trustees presented the deed for Port Arthur College to the Lamar University Board of Regents. Classes began on the Port Arthur campus on Aug. 28, 1975. Since the merger in 1975, enrollment increased from 151 students to a peak of more than 3,000 and the curriculum has been expanded to more than 50 areas of study. In 1977, the 65th Legislature approved House Bill 1134 renaming the campus as Lamar University-Port Arthur; the "Extension Center" designation was dropped. In 1983, the 68th Legislature passed three bills which directly affected the college:

  1. Senate Bill 409 in effect deleted the restrictive language of H.B. 130 (passed in 1971 by the 63rd Legislature), thereby making Lamar University-Port Arthur eligible, on an equal basis with other state institutions, for state funds to be utilized in the purchase of land and/or buildings.
  2. Senate Bill 410 provided Lamar University regents with the authority to levy a fixed student fee and the authority to bond against said fee for construction of a student center building on the Port Arthur campus. This legislation was validated by a majority vote of the Lamar University-Port Arthur student body in November 1983.
  3. Senate Bill 620 created the Lamar University System. Lamar University-Port Arthur thus became a component institution of that system on Aug. 29, 1983.

In 1985, two bills affected the school:

  1. Senate Bill 578 in 1985 provided that Lamar University-Port Arthur should be renamed a beneficiary institution and receive funds through the Higher Education Assistance Fund.
  2. The General Appropriations Act of 1985 directed that a formula be developed by the Texas Higher Education Coordinating Board to provide operational funding to Lamar University-Port Arthur on the same basis as other state-supported institutions of higher education.
    • Senate Bill 78 in 1989 removed restrictions imposed by earlier legislation on the acquisition of real estate and the construction of facilities on campus.
    • Senate Bill 843 in 1991 clarified the issue of degree-granting authority by granting permission for Lamar University-Port Arthur to issue associate degrees in its own name. Effective Sept. 1, 1995, by action of the Texas Legislature, the Lamar University System was abolished and Lamar University-Port Arthur along with sister institutions in Orange and Beaumont joined The Texas State University System. With offices in Austin, TSUS includes Sam Houston State University, Texas State University, and Sul Ross State University.

House Bill 1297 was signed into law in June 1999, changing the name of the institution to Lamar State College-Port Arthur.

Lamar State College Port Arthur is a member of The Texas State University System and an equal opportunity/affirmative action educational institution.