Arsonoliposomes (ARSL) constitute a particular class of liposomes that incorporate arsonolipids (ARS) into their membranes. ARSL realize selective toxicity to cancer cells; thus, they are an important tool in the treatment of cancer. Folic acid (FA) is widely used in targeted drug delivery due to its high affinity for the folate receptors that are overexpressed in cancer cell membranes. The aim of our studies was to develop novel triple-negative breast cancer (TNBC)-targeted ARSL by incorporating folic acid-conjugated polyethylene-glycol PEG-lipid (FA-PEG-lipid) into their membrane and loading them with anticancer drug doxorubicin (DOX). ARSL incorporating 0.1 mol% of FA-PEG-lipid were prepared and loaded with DOX, using the active loading protocol. They were characterized for their size distribution, zeta potential and drug entrapment efficiency (%). Their cytotoxic activity towards TNBC cell lines, particularly MDA-MB-231 (epithelial human breast cancer cells) and MCF7 (human breast cancer cells), was evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT-assay. The first results demonstrated enhanced toxicity of this novel type of ARSL towards cancer cells, which is particularly interesting and deserves further exploitation.