Abstract: Green algae Ulva grow widely along the coastline of China Zhejiang Province is a major province which makes use of Ulva Its products not only supply the domestic but also the international market Common Ulva samples were collected from different locations in different times in 2011， including inner bay of Xiangshan， Fenghua and open sea island Gouqi Identification was conducted by combining morphological observation and molecular biological methods The results showed that dominant species in Xiangshan and Fenghua from January to March was Ulva prolifera， cohabitating with Ulva linza and Ulva flexuosa However， in Gouqi Island Ulva pertusa and Ulva fasciata were more common.

Key words: Xiangshan, Fenghua, Gouqi Island, Ulva, morphology, molecular identification