Hilda Catharina Petrini (9 October 1838, Stockholm – 30 January 1895, Stockholm) was a Swedish watchmaker. She has been referred to as the first female master of mechanic of her country.
Hilda Petrini belonged to a wealthy old merchant family of Italian descent in Stockholm. During her youth, Petrini was skillful swimmer and for a time assisted Nancy Edberg during her swimming lessons for Louise of the Netherlands and Louise of Sweden. In 1858, Petrini was accepted as a student i mechanics under Chronometer watch maker Söderberg. She made her apprenticeship with good result and was for a time the assistant manager of the Söderberg factory. She was offered a position at the Royal Observatory, Greenwich, but her parents did not wish for her to move so far away. In 1862, Hilda Petrini applied for a license to establish her own clock maker factory in Stockholm. Her application was controversial for the city guild: not because of her gender, but because of her combined gender and civil status, as the guild normally only issued licenses to widows, not unmarried women, although there was no law to forbid it. She was therefore denied a license, formally because of her age. Instead, her mother, now a widow, applied for a license and was immediately granted one. Hilda Petrini thereby opened her own clock factory by use of her mother's license. She was a successful and recommended craftswoman and took apprentices of both genders.