This is an 18.7 percent growth over the same period last year, Xinhua reported.
The Sri Lanka Tourism Development Authority said western Europe accounted for 172,602 tourists.
Britain contributed 47,975 tourists, followed by Germany at 32,081.
The largest growth percentage came from Spain. Spanish tourists rose by an impressive 89.2 percent, from 2,058 in 2011 to 3,894 this year.
The number of South Asian tourists was 116,717.
India sent 85,426 tourists. The Maldives showed a 6.7 percent growth with 20,602 tourists, the tourism authority said in its monthly bulletin.
Tourists from East Asia grew 36.7 percent from 41,340 in the first half of 2011 to 56,497 this year.
The number from Japan increased by 29.4 percent to 10,203 while Chinese tourists totalled 9,622, a 11.7 percent increase from 8,613 in 2011.
Sri Lanka has set an ambitious target of attracting one million tourists this year, and expects it to rise to 2.5 million by 2016. The industry is tipped to earn around USD 2 billion this year. (IANS)