Coenzyme Q (or ubiquinone) is a redox-active lipid, which serves as universal electron carrier in the mitochondrial respiratory chain and antioxidant in the plasma membrane limiting lipid peroxidation and ferroptosis. Mechanisms allowing cellular coenzyme Q distribution after synthesis within mitochondria are not understood. Here, we identify the cytosolic lipid transfer protein STARD7 as a critical and limiting factor of intracellular coenzyme Q transport. Dual localization of STARD7 to the intermembrane space of mitochondria and the cytosol upon cleavage by the rhomboid protease PARL ensures the synthesis of coenzyme Q in mitochondria and its transport to the plasma membrane. While cytosolic STARD7 overexpression protects against ferroptosis, it limits CoQ abundance in mitochondria and respiratory cell growth, illustrating the need to coordinate CoQ synthesis and cellular distribution by PARL-mediated STARD7 processing. Our findings highlight the antioxidant function of mitochondrial CoQ against ferroptosis and identify PARL and STARD7 as promising targets to interfere with ferroptosis. The repository contains raw files and methods for project 0112 (brain – whole proteomics) and 0176 (spatial proteomics). The labeling of the raw files and the experiment – raw file matches are available in the individual search zip files. The individual sections are accompanied with the project identifier.