[en] Production of polyhydroxybutyrate (PHB), a biodegradable plastic, in plant, has been studied all over the world. We have constructed a transform tion vector pLSP15 carrying the PHB biosynthesis genes. Each of PHB genes was driven by an oil palm leaf-specific promoter (LSP1). This tran formation vector was later transformed into Arabidopsis thaliana and successfully produced T_3 putative transgenic plants. The mature T_3 generation was analysed by Reverse Transcription-qPCR (RT-qPCR) to test the capability of a monocotyledon oil palm LSP1 promoter in driving the expression of the PHB genes in a dicotyledon A. thaliana plant. Expression of all PHB genes, for example phbA (2.32), phbB (1.53) and phbC (1.47) relative to the wild-type, were detected in the plant. Nile blue A staining demonstrated that the PHB polymer was successfully produced throughout the deve o mental stage of the transgenic A. thaliana plant without any deleterious effects. The results demonstrated that the oil palm LSP1 promoter could drive the expression of the PHB biosynthesis genes in plants. (author)