Oliba Seledina Nieves Arroyo (born 1977-11-25 in Esmeraldas) is a female weightlifter from Ecuador.

She won a gold medal at the 2007 Pan American Games for her native South American country in the + 75 kg weight division.

Nieves won the gold medal of the 2007 Pan American Games +75 kg category.

[1] She won the gold medal of the 2012 Pre-Olympic Championship held in Guatemala, winning the berth to the 2012 Summer Olympics.

[3] Nieves also won the bronze medal in the 2013 Bolivarian Games in Trujillo, Peru.