I don't know if you mean bed pillows or decorative pillows so here is what I came up with
You can wash your bed pillows with a mild detergent in the gentle cycle. You might want to run it in the rinse cycle afterwards to get rid of detergent residue.
You can wash pillows at home in your wash machine but I have never had really good luck at home because they come out lumpy and odd shaped. I work for a large resort doing laundry and we wash the pillows in a large commercial machine with a load of towels. The pillows come out beautifully in the large commercial washer and dryer! I wonder if it's because the drums are so much bigger and there's more room for them to move around and the higher heat of the commercial dryer dries them better. I hold my breath every time I wash pillows at work but I haven't ruined any yet!
Use oxiclean and put them in the washer dryer once per season.