Kanstantsin Siamionau

{{Short description|Belarusian judoka (born 1978)}}

{{Use dmy dates|date=April 2024}}

{{Infobox judoka

| image =

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| country = Belarus

| weight_class = {{nbnd}}73 kg

| rank =

| rank_ref =

| dan =

| worlds_rank = 7

| worlds_year = 2007

| worlds_weight = Men's 73 kg

| regionals_type = EU

| regionals_rank = 3

| regionals_year = 2007

| regionals_weight = Men's 73 kg

| nationals =

| olympics_rank = 13

| olympics_year = 2008

| olympics_weight = Men's 73 kg

| show-medals =

| medaltemplates =

{{Medal|Sport| Men's judo }}

{{Medal|Country| {{BLR}} }}

{{Medal|Competition| European Championships }}

{{Medal|B| 2007 Belgrade | {{nbnd}}73 kg }}

{{Medal|Competition| European Junior Championships }}

{{Medal|S| 1997 Ljubljana | {{nbnd}}71 kg }}

{{Medal|Competition| Summer Universiade }}

{{Medal|B| 2001 Beijing | {{nbnd}}73 kg }}

| updated = 17 November 2022

}}

Kanstantsin Siamionau (born 22 October 1978) is a Belarusian judoka.