The 5th South American Youth Championships in Athletics were held in Montevideo, Uruguay from November 11–13, 1978.

Medal winners are published for boys[1] and girls.

[2] Complete results can be found on the "World Junior Athletics History" website.

[3] *   Host nation (Uruguay) Detailed result lists can be found on the "World Junior Athletics History" website.

[3] An unofficial count yields the number of about 179 athletes from about 7 countries: