| Sonja Johnsson | |
| Fullname: | Sonja Sofia Valfrida Johnsson |
| Nationality: | Swedish |
| Strokes: | Freestyle |
| Club: | Stockholms KK |
| Birth Date: | 1895 8, df=yes |
| Birth Place: | Stockholm, Sweden |
| Death Place: | Stockholm, Sweden |
Sonja Sofia Valfrida Johnsson (later Dymling, 7 August 1895 – 18 June 1986) was a Swedish freestyle swimmer who competed in the 1912 Summer Olympics.[1] She was eliminated in the first round of the 100 m event and finished fourth with the Swedish 4 × 100 m team.
Her nephew Stein competed for Norway in the discus throw at the 1948 and 1952 Olympics.