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Many parasitic plants are characterized by having specialized organs（i.e.haustoria） which they use to obtain water and/or nutrients from host plants.There are around 4000 parasitic flowering species placed in 12 orders and 19 families.Of them,about 90% of parasitic species（in four orders） retain photosynthetic capability（hemiparasites）,while 10% of parasitic species（in 10 orders） have lost photosynthetic capability（holoparasites）.In free-living plants,the plastome is very conserved in size（120 – 170 kb）,gene contents（110 –130 genes） and a quadripartite structure（LSC,IRA,SSC and IRB）.Loss of photosynthetic capability in holoparasites is often correlated with degradation or loss of photosynthesis-related and other non-housekeeping genes.Of the parasitic lineages,Orobanchaceae（Lamiales） is the only family including autophytes,hemiparasites and holoparasites.Therefore,this family was considered as an ideal model to investigate evolution of the characters related to parasitism.In this study,we sampled more than 100 species of Orobanchaceae representing all recognized clades of this family.The genome skimming data was used to assemble plastome using GetOrganelle pipeline（https://github.com/Kinggerm/GetOrganelle）.Our results showed that gene translocations and IR expansion happened in some hemiparasites and photosynthesis-related genes were lost in holoparasites.Based on the dated phylogeny of Orobanchaceae,we found that gene/genome reduction is high associated with origin age of the holoparasitic lineage.Therefore,the results indicated that relax selection may facilitate pseudogenization of plastid genes,then be fully "kick out",and house-keeping genes may eliminate "in the future".