In　this　work,　an　intermediate　layer　of　Mo　is　pre-deposited　on　the　flexible　Mo　foil　before　the　deposition　of　Cu2ZnSnS4　(CZTS)　thin　film　to　optimise　the　characteristics　of　the　flexible　CZTS　thin　film　solar　cell　(TFSC).　It　is　confirmed　that　the　pre-deposition　of　the　Mo　layer　leads　to　the　improvement　in　the　degree　of　the　interface　matching　between　the　back　electrode　and　the　CZTS　thin　film　which　is　always　regarded　as　the　main　recombination　centres　of　the　carriers　in　the　solar　cell.　By　employing　a　Mo　interlayer　between　the　Mo　foil　and　CZTS　layer,　the　conversion　efficiency　of　the　as-fabricated　(Mo　foil/Mo/CZTS/CdS/i-ZnO/AZO/Ni/Al)　solar　cell　is　further　increased　from　1.27　to　1.46%.　Meanwhile,　the　traditional　structure　(soda-lime　glass/Mo/CZTS/CdS/i-ZnO/AZO/Ni/Al)　CZTS　TFSC　acted　as　a　matched　group　which　is　also　prepared　and　obtained　a　conversion　efficiency　of　1.58%.　This　work　demonstrates　for　the　first　time　the　effects　of　Mo　intermediate　layers　in　the　flexible　CZTS　TFSCs.　©　2017　The　Institution　of　Engineering　and　Technology.