Born in San Cristóbal, Táchira, Villanueva was a Deportivo Táchira youth graduate. On 3 March 2013 he made his professional debut, starting in a 0–1 away loss against Estudiantes de Mérida.

After being rarely used, Villanueva moved to fellow Primera División team ACD Lara in 2014. He scored his first professional goal on 25 January 2015, netting the game’s only in an away win against Carabobo FC.

On 22 February 2015, Villanueva scored a brace in a 3–1 home win against Trujillanos FC. He finished the campaign with 20 appearances and four goals.

On 4 July 2015 Villanueva joined Málaga CF, being assigned to the reserves in Tercera División. On 3 May 2016, he was bought outright by the club, signing a permanent three-year deal and being promoted to the main squad in La Liga.

Villanueva made his debut in the main category of Spanish football on 16 October 2016, starting in a 1–1 away draw against Deportivo Alavés. The following 10 August he renewed his contract until 2020, and was immediately loaned to Segunda División club Cádiz CF for one year.

On 20 January 2016, Villanueva was called up to the Venezuela national team for a friendly against Costa Rica. He made his full international debut on 2 February, starting in the 1–0 win in Barinas.

Villanueva scored his first international goal on 24 March 2016, netting the second in a 2–2 away draw against Peru following an assist from Málaga teammate Juanpi. He was named in the Vinotinto’s squad for the year’s Copa América Centenario in the United States, but did not play.

On 24 July 2018, Villanueva joined fellow second division side CF Reus Deportiu, on a season-long loan. On 28 December, he was one of the five players who left the club due to unpaid wages.

On 9 January 2019, Villanueva moved to Gimnàstic de Tarragona still in the second tier, on loan until June.