Luxembourg was represented at the 2000 Summer Olympics in Sydney, Australia by the Luxembourg Olympic and Sporting Committee.
In total, six athletes represented Luxembourg in four different sports including swimming, table tennis, tennis and triathlon.
Swimming
Three Luxembourger athletes participated in the swimming events – Alwin de Prins in the men's 100 m breaststroke, Luc Decker in the men's 100 m butterfly and Lara Heinz in both the women's 50 m and 100 m freestyle.
The heats for the men's 100 m breaststroke took place on 16 September 2000 at 4:45pm. De Prins contested heat five and started in lane three. He finished third in his heat in a time of 1 minutes 4.37 seconds which was ultimately not fast enough to qualify for the semi-finals.
The heats for the women's 100 m freestyle took place on 20 September 2000 at 3:02pm. Heinz contested heat three and started in lane two. She finished fourth in her heat in a time of 58.55 seconds which was ultimately not fast enough to qualify for the semi-finals.
The heats for the men's 100 m butterfly took place a day later on 21 September 2000 at 4:22pm. Decker contested heat three and started in lane six. He finished fourth in his heat in a time of 56.1 seconds which was ultimately not fast enough to qualify for the semi-finals.
The heats for the women's 50 m freestyle took place a day later on 22 September 2000 at 3:02pm. Heinz contested heat six and started in lane five. She finished fifth in her heat in a time of 26.55 seconds which was ultimately not fast enough to qualify for the semi-finals.
;Men
{|class=wikitable style="font-size:90%"
|-
!rowspan="2"|Athlete
!rowspan="2"|Event
!colspan="2"|Heat
!colspan="2"|Semifinal
!colspan="2"|Final
|-style="font-size:95%"
!Time
!Rank
!Time
!Rank
!Time
!Rank
|-align=center
|align=left|Alwin de Prins
|align=left|100 m breaststroke
|1:04.37
|39
|colspan=4|Did not advance
|-align=center
|align=left|Luc Decker
|align=left|100 m butterfly
|56.10
|47
|colspan=4|Did not advance
|}
;Women
{|class=wikitable style="font-size:90%"
|-
!rowspan="2"|Athlete
!rowspan="2"|Event
!colspan="2"|Heat
!colspan="2"|Semifinal
!colspan="2"|Final
|-style="font-size:95%"
!Time
!Rank
!Time
!Rank
!Time
!Rank
|-align=center
|align=left rowspan=2|Lara Heinz
|align=left|50 m freestyle
|26.55
|34
|colspan=4|Did not advance
|-align=center
|align=left|100 m freestyle
|58.55
|37
|colspan=4|Did not advance
|}
Table tennis
Two Luxembourger athletes participated in the table tennis events – Ni Xialian in both the women's singles and women's doubles and Peggy Regenwetter who partnered Ni in the women's doubles.
Ni received a bye in the group stage for the women's singles. Round one took place on 20 September 2000 and Ni defeated Csilla Bátorfi of Hungary 24–22, 21–10, 19–21, 21–23, 21–14. Round two took place the following day but Ni lost 21–15, 21–11, 21–15 to Li Ju of China.
{| class="wikitable" style="font-size:90%"
!rowspan="2"|Athlete
!rowspan="2"|Event
!colspan=3|Group Stage
!Round of 32
!Round of 16
!Quarterfinals
!Semifinals
!colspan=2|Final /
|-style="font-size:95%"
!Opposition<br />Result
!Opposition<br />Result
!Opposition<br />Result
!Opposition<br />Result
!Opposition<br />Result
!Opposition<br />Result
!Opposition<br />Result
!Opposition<br />Result
!Rank
|-align=center
|align=left|Ni Xialian
|align=left|Women's singles
|colspan=3
|<br/>W 3–2
|<br/>L 0–3
|colspan=4|Did not advance
|-align=center
|align=left|Ni Xialian<br/>Peggy Regenwetter
|align=left|Women's doubles
|colspan=3
|<br/>L 2–3
|colspan=5|Did not advance
|}
Tennis
One Luxembourger athlete participated in the tennis events – Anne Kremer in the women's singles.
{|class=wikitable style="font-size:90%"
|-
!rowspan="2"|Athlete
!rowspan="2"|Event
!Round of 64
!Round of 32
!Round of 16
!Quarterfinals
!Semifinals
!colspan=2|Final /
|- style="font-size:95%"
!Opposition<br />Score
!Opposition<br />Score
!Opposition<br />Score
!Opposition<br />Score
!Opposition<br />Score
!Opposition<br />Score
!Rank
|-align=center
|align=left|Anne Kremer
|align=left|Women's singles
|<br/>W 6–2, 6–4
|<br/>L 6–4, 3–6, 4–6
|colspan=5|Did not advance
|}
Triathlon
One Luxembourger athlete participated in the triathlon events – Nancy Kemp-Arendt in the women's race.
{| class="wikitable" style="font-size:90%"
|-
!Athlete
!Event
!Swim (1.5 km)
!Trans 1
!Bike (40 km)
!Trans 2
!Run (10 km)
!Total Time
!Rank
|-align=center
|align=left|Nancy Kemp-Arendt
|align=left|Women's
|19:15.18
|27.60
|1:05:17
|26.30
|37:48.86
|2:03:14.94
|10
|}