| Jacek Kościelniak | |
| Nationality: | Polish |
| Office: | member of Sejm 2005-2007 |
| Term Start: | 25 September 2005 |
| Term End: | ? |
| Party: | Law and Justice |
Jacek Zygmunt Kościelniak (born 9 October 1963 in Dąbrowa Górnicza) is a Polish politician. He was elected to the Sejm on 25 September 2005, getting 3,765 votes in 32 Sosnowiec district as a candidate from the Law and Justice list.