The ceasefire violation took place within two days of Nawaz Sharif being sworn in as prime minister of Pakistan.
The source said that the killed soldier has been identified as Lance Naik Bachan Singh. Indian troops returned the Pakistani firing, he added.
"An Indian post, Khalsa 2, along the LoC in the Saujian sector (about 260 km north-west of Jammu) came under fire from Pakistani troops at 1.35 pm today (Friday). The firing, in which heavy machine guns and rocket-propelled grenades were used, lasted for about an hour during which an Indian Army soldier was killed," the army source said.
A Brigadier was injured May 24 when an Indian post in the Nowgam sector of Kupwara district in Kashmir Valley was fired at by Pakistani troops in violation of the ceasefire agreement between India and Pakistan.
Over two dozen ceasefire violations by Pakistan have taken place this year. In 2012, the number of ceasefire violations were 117 against 61 in 2011. The firing by Pakistan across the Line of Control mainly takes place to provide cover to infiltrating militants.
Nawaz Sharif, who has assumed office as prime minister of Pakistan, had Thursday affirmed to progressively pursue normalcy in ties with India while seeking solution to Kashmir and other outstanding issues.
He had said that neighbours will be focus of his immediate attention.