The bank said it earned $104.1m in the first three months, a record level according to Reuters data.
Gulf Bank, Kuwait's third-largest lender by market value, boosted profit in the first quarter by 26%.
The bank said on Sunday it earned 30.1 million dinars ($104.1 million) in the first three months, a record level according to Reuters data.
Analysts at Global Investment House had forecast first quarter profit of 27.49 million dinars in a Reuters survey in March. It had posted 23.9 million dinars in the first quarter 2006.
It gave no explanation for the earnings rise, which came a week after National Bank of Kuwait, the country's biggest lender, posted a 13.5% rise in first-quarter profit.
Earnings per share (EPS) were 28.3 fils in the first quarter compared to 22.2 fils in the same quarter a year ago, according to a statement posted on the bourse website after trading hours. There are 1,000 fils to the dinar.
The share closed unchanged at 1.6 dinars.
Gulf Bank, established in 1960, has 38 branches in Kuwait where it faces strong competition from players such as NBK or Commercial Bank of Kuwait.
It offers retail, corporate and investment banking services, according to its website.