In 1969, the Republican Decree No. (1088) was issued to establish some new faculties that would be affiliated to the universities of Cairo, Ain Shams, Alexandria and Assuit. Among these faculties was Tanta Faculty of Science that was affiliated to Alexandria University.

Then on December 22, 1969, the Ministerial Decree No. 654 was issued stating applying the bylaw of Faculty of Science, Alexandria University on Faculty of Science, Tanta University. Upon this, the Faculty would be consisted of six practical departments: 1- The Department of Mathematics
2- The Department of Physics
3- The Department of Chemistry
4- The Department of Geology
5- The Department of Botany
6- The Department of Zoology
.

After that, upon the Universities Organization Law No. 49 in 1972, Tanta University has been established and has become dependent from Alexandria University.

- On Saturday, October 11, 1969, the academic and practical study has begun in the Faculty at Saint Louis School Building (University Administration now). - Then it was moved to the building of Faculty of Medicine (Faculty of Education now).
- After that, in 1978, the University began to establish the new building of the Faculty in the Medical Campus.
Completing the building in the academic year 1993/1994, Faculty of Science has become a great scientific institute in the campus of the scientific faculties and the faculty has become rich with all the educational and research potentials.

Consequently, on Wednesday, July 28, 1993, Prof. Hussain Kamel Bahaa El-Deen, Minister of Education, has inaugurated the building after completing all its facilities which included four basic wide annexes for the scientific departments with their student and research laboratories and the offices of the teaching staff members. Moreover, there is a fifth separate annex that consists of three floors one of them is allocated for the library and the others are for the Faculty administration. Furthermore, there are workshops and stores for the Faculty in a separate building.
Finally, on October 27, 1999, the Ministerial Decree No. 1344 has been issued to modify the bylaw of Faculty of Science as follows:
1- Modifying the name of the Department of Mathematical Statistics to be Mathematical Statistics and Computer Sciences. 2- Teaching computer to all the departments and divisions in the Faculty.
3- Teaching computer to all diploma divisions granted by the Faculty.
4- Teaching computer to all masters divisions granted by the Faculty.