Kierzek

{{Infobox settlement

| name = Kierzek

| settlement_type = Village

| total_type =  

| image_skyline =

| image_caption =

| image_flag =

| image_shield =

| image_map =

| subdivision_type = Country

| subdivision_name = {{POL}}

| subdivision_type1 = Voivodeship

| subdivision_name1 = Masovian

| subdivision_type2 = County

| subdivision_name2 = Ostrołęka

| subdivision_type3 = Gmina

| subdivision_name3 = Kadzidło

| pushpin_map = Poland

| coordinates = {{coord|53|14|N|21|19|E|region:PL|display=title,inline}}

| elevation_m =

| population_total =

| website =

}}

Kierzek {{IPAc-pl|'|k|J|e|ż|e|k}} is a village in the administrative district of Gmina Kadzidło, within Ostrołęka County, Masovian Voivodeship, in east-central Poland.{{TERYT}} It lies approximately {{convert|10|km|mi|0|abbr=on}} west of Kadzidło, {{convert|25|km|mi|0|abbr=on}} north-west of Ostrołęka, and {{convert|115|km|mi|0|abbr=on}} north of Warsaw.