We report here the first comprehensive dataset derived by using high-throughput sequencing technology (Illumina) for Sacha inchi. Transcriptome analyses from two developmental stages (the initial stage of seed development and the fast oil accumulation stage) of Sacha Inchi seeds revealed 70,392 unigenes. Expression of 22,179 unigenes differed at least 2-fold between the two libraries. Transcriptome sequences were annotated with Gene Ontology and KEGG Orthology identifiers. Functional categorization of differentially expressed genes reflected a number of important pathways, including the de novo FA biosynthesis, TAG assembly and the formation of PUFAs. Focusing on lipid genes, we identified 397 unigenes associated with the de novo FA biosynthesis, TAG assembly and the formation of PUFAs from Sacha Inchi seeds. These unigenes provide the foundation for further studies on molecular mechanisms underlying oil accumulation and PUFA biosynthesis in Sacha Inchi seeds. In particular, those candidate genes (such as SAD, FAD2, FAD3) associated with PUFA biosynthesis would provide critical clues to reveal the molecular mechanisms underlying the high levels of α-linolenic acid biosynthesis in Sacha Inchi seeds.