The crimes were committed between 2002 and 2007.
The girls, now aged 18 and 21, lived on the same street as the man, who also had a relationship their mother. The girls became friends with the man’s children, newspaper Vestmanlands Läns Tidning (VLT) reports.
The man abused the girls regularly over a period of several years.
The most serious crime of which the man was found guilty was a case of aggravated rape in 2004 when he forced the younger girl — then aged 14 — into his car. There he tied her hands and feet, took her to an isolated place and raped her.
Västerås District Court sentence the man to nine years in prison and ordered him to pay the younger sister 350,000 kronor ($58,000) in compensation.
The man currently lives with the older of the two sisters, according to VLT.