The incident took place around 2pm on Wednesday at Los Alemanes beach, just south of the village of Zahara de los Atunes, in the province of Cadiz.
In footage of the incident filmed by one onlooker, beachgoers can be seen playing in the water as the inflatable dinghy comes ashore. Dozens of people pour out of the craft and scramble ashore, jumping into the shallow waters even before the boat has been pulled up onto the sand.
Local newspaper Diario De Cadiz reports that many of those on board quickly changed their clothing to evade the police, who carried out searches to apprehend the suspected illegal migrants.
Many of the group were collected in vehicles after landing, according to the paper. Those driving the vehicles could potentially face human trafficking charges if caught.
The beach is just over 30km (19 miles) from the north African coast. A similar landing also took place in a nearby beach at Sierra del Retín.
Beaches along Spain’s Costa de la Luz are regular landing sites for migrants travelling from north Africa. El Mundo reportsthat 149 migrants were rescued by maritime rescue vessels over the course of one weekend at the end of July.
More than 1,700 have been rescued from the water so far this year, with the month of June alone seeing more than 900.