On the day of the Declaration of Independence – May 15, 1948 – the Egyptian Army invaded the newly-founded state and Nirim was the first Israeli settlement to be attacked. The kibbutz was heavily shelled by Egyptian artillery, which claimed the lives of eight members and left its grounds in ruins. The other members took shelter in underground dugouts and warded off the armored attack using nothing but small-arms fire. Despite its great superiority in men and weapons, the Egyptian Army eventually retreated with heavy losses.

After the war, the kibbutz moved some 20 kilometers north to its present site, on the Gaza Strip border. Over the years the kibbutz grew and its population expanded: children were born and other members of Hashomer Hatzair from Israel Australia, and South America joined its ranks.

Nirim's livelihood is founded primarily on agriculture. The various field crops are spread over 20,000 dunams (5,000 acres) and employ a highly professional staff, largely from within the kibbutz. Other agricultural branches like the avocado orchard, the dairy and the hothouses, annually yield some of the best results in the country and Nirim is one of the largest organic farms in Israel. The kibbutz is also part-owner of the Nirlat paint factory.

Many of the members work outside the kibbutz and pursue professions in the fields of education, psychology, academia, engineering, high-tech and agriculture.

Today Nirim is home to some 400 people, including about 180 members, 180 children and 40 residents, who enjoy the rich cultural and social life and a green environment.