Video footage filmed by a beach-goer shows the moment dozens of men sprinted across the beach after a black dinghy washed up at about 2pm on Wednesday.
Confused tourists are seen standing around as the men leap out of the tiny boat after it reaches shallow water.
The incident happened on Germans’ Beach – Playa de los Alemanes in Spanish – near the resort of Tarifa in southern Spain.
The men are believed to have crossed the Straits of Gibraltar from Morocco.
Most of them reportedly disappeared after reaching dry land, while a number stayed behind to drag the boat onto the shore.
Only one officer from the Civil Guard was in the area at the time, police said, meaning they were unable to stop the beach drop.
The whereabouts of the immigrants now was not immediately clear.
Migrants arriving onto Spanish beaches are not common but appear to be on the up.
The number of migrants reaching the province of Malaga in the first six months of this year was 749 people, almost equalling the number for the whole of the previous year.
The incident came just hours after 15 migrants on two boats were rescued in the Mediterranean in the eight mile stretch of water between southern Spain from Morocco.
