Mariusz Siembida

{{short description|Polish swimmer}}

{{Infobox swimmer

| name=Mariusz Siembida

| image=

| imagesize=

| caption =

| fullname = Mariusz Siembida

| nicknames =

| nationality = {{POL}}

| strokes = backstroke

| club = KS Lublinianka

| collegeteam =

| birth_date = {{birth date and age|1975|3|21|df=y}}

| birth_place = Puławy, Lubelskie

| death_date =

| death_place =

| height = {{height|m=1.88|precision=0}}

| weight =

| medaltemplates=

{{MedalSport | Men's swimming}}

{{MedalCountry | {{POL}} }}

{{MedalCompetition|World Championships (SC)}}

{{MedalSilver | 1999 Hong Kong | 50 m backstroke}}

{{MedalBronze | 1999 Hong Kong | 100 m backstroke}}

{{MedalCompetition|European Championships (LC)}}

{{MedalBronze| 1997 Seville | 4×100 m medley}}

{{MedalBronze| 1999 Istanbul | 50 m backstroke}}

{{MedalCompetition|European Championships (SC)}}

{{MedalGold| 1996 Rostock | 50 m backstroke}}

{{MedalGold| 1996 Rostock | 100 m backstroke}}

{{MedalCompetition|Summer Universiade}}

{{MedalGold | 2001 Beijing | 50 m backstroke}}

{{MedalBronze | 1997 Catania | 100 m backstroke}}

}}

Mariusz Siembida (born 21 March 1975 in Puławy, Lubelskie) is a retired backstroke swimmer from Poland, who competed for his native country at two consecutive Summer Olympics, starting in 1996 (Atlanta, Georgia).

A member of Lublinianka he is best known for winning the bronze medal at the 1997 European Swimming Championships in the men's 4×100 m medley relay, alongside Marek Krawczyk, Marcin Kaczmarek and Bartosz Kizierowski.