The PMADS9 is a member of the AGL15 subfamily of MADS-box genes. The Arabidopsis AGL15 subfamily genes have been reported to act as inhibiters of flower senescence, repressors of floral transition and enhancers of somatic embryo development. Using YADE method and hiTAIL-PCR, we isolated 1853bp sequences upstream of the putative translation start of the PMADS9 gene from petunia. The results of 5′RLM-RACE analysis showed that the PMADS9 gene has at least 4 TSSs, and 2 of them are located in the first exon. Cis-regulatory elements of the PMADS9 promoter predicted by PLACE and PlantCARE are related with seed and pollen development and environmental response. Analysis of promoter sequences from AGL15-clade MADS-box genes by FootPrinter showed that there are very conserved RY-repeat motifs among them, and the conversation of promoters between Solanaceae and the selected 5 species of Rosids is higher than that between Brassicaceae and the same selected species，even though Solanaceae is less closely related to Rosids than Brassicaceae. Furthermore, the results also suggested that regions of 200-400bp and 800-1000bp upstream of the ATG were functionally important.