The study of angiospermic plants is based on deep knowledge of all the external characteristics of plants. To know the natural resources of the earth one requires vast understanding of plants. The flower is a modified shoot with highly compressed internodes and closely crowded floral leaves. Flower is the very important characteristics feature of seed plant. Among the angiospermic plants there is a great variation in size, shape, its arrangement, essence and color. Flower consists of calyx, corolla, androecium and gynoecium. It is intended to provide sufficient information to understand the all the features of any flower. The book consists of the scientific description of fundamental units of flower, such as bract, calyx, corolla, androecium and gynoecium and its modifications. The types of arrangement of floral parts in flower are helpful in identification and systematic arrangement of respective plant. The study of external features of all the parts of flower and its modifications are described in technical language for understanding of students and teachers of all concern fields.