1969–70 South-West Indian Ocean cyclone season

The 1969–70 South-West Indian Ocean cyclone season was an active cyclone season.

Severe Tropical Storm Aline
Aline existed from August 19 to August 22.

Tropical Cyclone Blanche
October 7 to October 15.

Moderate Tropical Storm Corrine
26 deaths in Comoros and Mozambique.

Moderate Tropical Storm Delphine
Delphine existed from December 29 to January 1.

Tropical Cyclone Diane–Francoise
This system entered the basin on January 7 and dissipated on January 17.

Moderate Tropical Storm Eliane
The storm struck western Madagascar, bringing rainfall.

Tropical Cyclone Genevieve
Four deaths in Madagascar due to flooding.

Tropical Cyclone Hermine
One death on Reunion.

Very Intense Tropical Cyclone Harriet-Iseult
Iseult existed from February 2 to February 15.

Very Intense Tropical Cyclone Josephine-Jane
It was named Josephine in its formative stages due to being in what was considered the Australian basin at the time.

Moderate Tropical Storm Katia
Katia existed from March 16 to March 26.

Tropical Cyclone Louise
Louise existed from March 20 to April 1.

Tropical Cyclone Kathy–Michelle
Michelle entered the basin on March 24 and dissipated on March 30.