Small urban street parks play an irreplaceable role in protecting ecological environment of cities and beautifying living spaces of citizens, in these parks plant is an essential landscaping element that can not only improve environmental quality, but also provide visual enjoyment for viewers. There are many small street parks in Zhanjiang City, however, plant landscapes in such parks lack in regional characteristics because of blind copy and random planting. By analyzing plant landscapes in typical street parks in Zhanjiang, and borrowing the theoretical research framework of linguistics, this paper concluded the vocabulary, sentence,chapter and grammatical rules of plant landscape design, in order to explore new methods for the plant landscape design of small parks in tropical coastal regions. Small urban street parks play an irreplaceable role in protecting ecological environment of cities and beautifying living spaces of citizens, in these parks plant is an essential landscaping element that can not only improve improve environmental quality, but also provide visual enjoyment for viewers. There are many small street parks in Zhanjiang City, however, plant blinds in the regional characteristics because of blind copy and random planting. By analyzing plant landscapes in typical street parks in Zhanjiang, and borrowing the theoretical research framework of linguistics, this paper concluded in the vocabulary , sentence, chapter and grammatical rules of plant landscape design, in order to explore new methods for the plant landscape design of small parks in tropical coastal regions.