Iolaus trimeni, the Trimen's sapphire, is a butterfly of the family Lycaenidae.

It is found in the southern Democratic Republic of the Congo, south-eastern Angola, Zambia, Tanzania, Malawi, Zimbabwe, Mozambique, Swaziland and South Africa.

In South Africa it is found from northern KwaZulu-Natal to Mpumalanga, Gauteng and the North West province.

In the cooler western part of its range there is a peak from September to January.

[3] The larvae feed on Tapinanthus oleifolius, T. quinquangulus, T. rubromarginatus and T. subulatus.