Socialist Students' Union of Sri Lanka (SSU) also known as Samajavadi Shishya Sangameya is a students' union in Sri Lanka that operates as the students' wing of the Marxist-Leninist Janatha Vimukthi Peramuna.
It is currently a member of the Inter-university Students' Federation.
The SSU was formed in 1968 by Marxist Rohana Wijeweera, initially called Samajawadi Sangamaya, the SSU is the oldest student union in Sri Lanka, and promotes Communism. It was able to start recruiting youths from both universities and independent student councils; by 1970 the SSU was dominant in student politics and was able to operate as the armed wing of the JVP in 1970 especially during the period of The United Front. Shanta Bandara was the founding general secretary of the Socialist Students Union. All the general secretaries who succeeded him (before 1990) were killed in the struggle by the United National Party government that was in power at that time, this included Lalith Wijayaratne, H. B. Herath, D. M. Ananda, Upali Jayaweera, Ananda Idamegama, Dr Nissanka, and Atula Senaratne. The SSU together with the Patriotic Students' Union were banned in 1988. After 1990, the Socialist Students Union was again reformed. Anura Dissanayake was its founding general secretary. Sunil Handunnetthi, Bimal Ratnayake and Mangala Kuruppu became general secretaries after him.