Recently, development of techniques to deliver pharmacologically active biomacromolecules such as peptides and proteins to cytosol has gained much interest. Here, we applied the peptide gemini (PG)-surfactants to a novel platform to design cell penetration lipopeptides (CP-PGs), which can deliver exogenous peptides and proteins to cytosol. Among the number of candidate CP-PGs having different peptide sequences at the X-, Y-, and Z-positions, we focused on those having two C12 alkyl chains appended to the side chain of two Cys residues, the betaine sequence -Asp-Lys-Asp-Lys-between the alkylated Cys residues (i.e., at the X-position), and having different cationic peptide sequences of oligo-Lys or oligo-Arg at the Y-and/or Z-positions. With respect to cytotoxicity for mammalian cells such as NIH3T3 cells upon 1 h exposure, those having (Lys) 3 (K 3 -DKDKC 12 and DKCK 12 -K 3 ) showed lower cytotoxicity (IC 50 = 241 and 198 μM) among those having oligo-Lys, (Lys) n (n = 1, 3, 5; IC 50 = 88−197 μM). Similar lower cytotoxicity was also observed for the CP-PG having two (Lys) 3 at both N-and C-terminal sides (K 3 -DKDKC 12 -K 3 ) (IC 50 = 225 μM). In contrast, the CP-PG having (Arg) 3 at the N-terminal side (R 3 -DKDKC 12 ) showed higher cytotoxicity (IC 50 = 88 μM). Carrier abilities of the CP-PGs for exogenous peptides were evaluated using the proapoptotic domain (PAD) peptide, which induces apoptosis by disturbing mitochondrial membranes after delivery into cytosol. As a result, the CP-PGs of K 3 -DKDKC 12 , DKCK 12 -K 3 , K 3 -DKDKC 12 -K 3 , DKCK 12 -K 5 , and R 3 -DKDKC 12 exhibited micromolar range carrier ability (the necessary half concentration to induce cell death (EC 50 ) by delivering PAD peptide to cytosol was 10, 6.2, 8.5, 5.8, and 11.5 μM, respectively). Especially, the carrier abilities of DKCK 12 -K 3 and DKCK 12 -K 5 were superior to the well-established cell penetration Arg-rich R8 peptide (EC 50 = 6.8 μM). Together, our results indicate that the PG-surfactant molecular framework could be a potential new platform to design efficient cell penetration carrier materials.