Alumni of the University of Karachi, Pakistan.

Notes:

• "Alumni" (see Alumnus) is used here in the (correct) broad sense, to include people who have spent a notable period of their career studying at the institution, not in a narrower, legal sense of having officially "graduated".
• In accordance with Wikipedia:Categories criteria, the period spent studying at the institution should be notable enough to be mentioned in the article.
• Recipients of honorary degrees are not included in this category.