Saillon (French pronunciation: [sajɔ̃]; Arpitan: Salyon) is a municipality in the district of Martigny in the canton of Valais in Switzerland.

Saillon is first mentioned in 1052 as castellum Psallionis. The municipality was formerly known by its German name Schellon, however, that name is no longer used.

Saillon has an area, as of 2009^[update], of 13.7 square kilometers (5.3 mi²). Of this area, 5.17 km² (2.00 mi²) or 37.6% is used for agricultural purposes, while 2.81 km² (1.08 mi²) or 20.5% is forested. Of the rest of the land, 1.12 km² (0.43 mi²) or 8.2% is settled (buildings or roads), 0.31 km² (0.12 mi²) or 2.3% is either rivers or lakes and 4.27 km² (1.65 mi²) or 31.1% is unproductive land.

Of the built up area, housing and buildings made up 3.3% and transportation infrastructure made up 3.1%. Out of the forested land, 16.8% of the total land area is heavily forested and 3.1% is covered with orchards or small clusters of trees. Of the agricultural land, 6.2% is used for growing crops, while 24.2% is used for orchards or vine crops and 7.0% is used for alpine pastures. All the water in the municipality is flowing water. Of the unproductive areas, 13.2% is unproductive vegetation and 17.9% is too rocky for vegetation.

The municipality is located in the Martigny district, on the right bank of the Rhône. It consists of the village of Saillon and exclave of Euloi.

The blazon of the municipal coat of arms is Argent a Tower Sable.

Saillon has a population (as of December 2020^[update]) of 2,818. As of 2008^[update], 19.7% of the population are resident foreign nationals. Over the last 10 years (2000–2010 ) the population has changed at a rate of 38.4%. It has changed at a rate of 34.1% due to migration and at a rate of 5.7% due to births and deaths.

Most of the population (as of 2000^[update]) speaks French (1,365 or 89.9%) as their first language, Portuguese is the second most common (85 or 5.6%) and German is the third (28 or 1.8%). There are 14 people who speak Italian.