Modesto Castillo (born 24 February 1959, in La Romana, Dominican Republic) is a former sprint and hurdling athlete who specialised in the 110 metres hurdles.

Castillo represented the Dominican Republic at the 1984 Summer Olympics in Los Angeles, United States, being eliminated in the first round of the 110 metres hurdles after finishing fifth in his heat. Four years later he competed for the Dominican team at the 1988 Summer Olympics in Seoul, South Korea. He qualified from his heat in the 110 metres hurdles before being eliminated in the quarterfinals.^[1]

Year	Competition	Venue	Position	Event	Notes
Representing the  Dominican Republic
1980	Central American and Caribbean Junior Championships (U20)	Nassau, Bahamas	1st	110 m hurdles	14.0
	Pan American Junior Championships	Nassau, Bahamas	4th	110 m hurdles	14.57
			6th	400 m hurdles	57.97
			5th	4 × 100 m relay	42.88
1981	Central American and Caribbean Championships	Santo Domingo, Dominican Republic	3rd	110 m hurdles	14.20
1982	Central American and Caribbean Games	Havana, Cuba	3rd	110 m hurdles	13.95
1983	Central American and Caribbean Championships	Havana, Cuba	2nd	110 m hurdles	13.79 (w)
	World Championships	Helsinki, Finland	13th (sf)	110 m hurdles	14.23
	Pan American Games	Caracas, Venezuela	4th	110 m hurdles	13.90
1984	Olympic Games	Los Angeles, United States	12th (h)	110 m hurdles	14.05
1985	World Indoor Games	Paris, France	19th (h)	60 m	6.85
			6th	60 m hurdles	7.86
1986	Central American and Caribbean Games	Santiago, Dominican Republic	4th	110 m hurdles	14.22
1987	Central American and Caribbean Championships	Caracas, Venezuela	3rd	110 m hurdles	14.06
			3rd	4 × 100 m relay	40.65
	Pan American Games	Indianapolis, United States	2nd	110 m hurdles	13.96
			6th	4 × 100 m relay	40.53
1988	Olympic Games	Seoul, South Korea	23rd (qf)	110 m hurdles	14.21
1996	Ibero-American Championships	Medellín, Colombia	–	110 m hurdles	DNF

• Athlete profile for Modesto Castillo at IAAF.org