- Saarlooswolfhond
- Sabueso Espanol (Spanish Hound)
- Sakhalin Husky
- Saluki
- Samoyed
- Sanshu Dog
- Sapsali
- Šarplaninac
- Schapendoes
- Schillerstovare
- Schipperke
- Schnauzer – divided into Miniature Schnauzer, Standard Schnauzer, Giant Schnauzer
- Schnoodle
- Schweizer Laufhund
- Schweizer Niederlaufhund
- Scottish Deerhound – see Deerhound
- Scottish Terrier
- Sealyham Terrier
- Segugio Italiano
- Seppala Siberian Sleddog
- Serbian Hound
- Serbian Mountain Hound
- Serbian Tricolour Hound
- Shar Pei
- Shetland Sheepdog
- Shiba Inu
- Shih Tzu
- Shikoku
- Shiloh Shepherd Dog
- Siberian Husky
- Silken Windhound
- Silky Terrier – see Australian Silky Terrier
- Sindh Mastiff – see Indian Mastiff
- Skye Terrier
- Sloughi
- Slovak Cuvac
- Slovakian Hound
- Slovensky Hrubosrsty Stavac (Ohar)
- Smalandsstovare
- Small Greek Domestic Dog – see Meliteo Kinidio
- Small Munsterlander
- Smooth Collie
- Smooth Fox Terrier – see Fox Terrier (Smooth)
- Soft-Coated Wheaten Terrier
- South Russian Ovtcharka
- Spanish Alano – see Alano Español
- Spanish Galgo – see Galgo Espanol
- Spanish Mastiff
- Spanish Water Dog
- Spinone Italiano
- Spitz — see Spitz for a list of Spitz-type breeds
- Springer Spaniel – see English Springer Spaniel or Welsh Springer Spaniel
- St. Bernard
- Stabyhoun
- Staffordshire Bull Terrier
- Standard Schnauzer
- Stephens Stock (Stephens Cur)
- Styrian Coarse-haired Hound
- Sussex Spaniel
- Swedish Elkhound – see Jämthund
- Swedish Lapphund
- Swedish Vallhund
- Swiss Shorthaired Pinscher