Newly filed accounts show that pre-tax profits increased from £203 million to £310.4 million in the year to December 31 2018.
JCB, which revealed in 2018 the global construction equipment market grew by 18 per cent compared with 2017, also saw turnover rise from £3.3 billion to £4.1 billion.
Known for its distinctive yellow machines found on building sites around the world, the privately-owned company has seen its global workforce grow to more than 11,000 strong.
JCB showed faith in its prospects with an increase in expenditure on research and development to £93.4 million last year.
However, the company has warned of a slowdown in the construction equipment sector spanning several emerging markets including the Middle East, Turkey and Latin America, with the exception of Brazil.
India, where JCB plans to open a new £65 million factory in Gujarat next year, is facing a temporary squeeze on funds for building projects.
A statement signed off by the board said: "Results in the early part of 2019 are in line with expectations.
"The global construction market is expected to grow in 2019, and the group's share of this market is also expected to grow.
"However, the rate of growth of individual markets will vary considerably, dependent upon local economic and geopolitical conditions.
"The group remains confident about its longer-term prospects and will continue to invest in its manufacturing and distribution base and in new product development throughout 2019 and beyond."
Speaking at the start of September, chief executive Graeme Macdonald said: "2018 was a very strong year for JCB during which the global construction equipment market grew by 18 per cent to an all-time high of one million machines.
"JCB outpaced this growth by increasing its sales revenue by 22 per cent last year, which was a very significant achievement.
"However, this growth has now stalled, with many markets softening this year, particularly the Middle East, Turkey, Latin America and India.
"We continue to make strategic investments in new product development and new manufacturing capacity to ensure JCB is ready to capitalise on future long-term growth opportunities."
JCB, which makes excavators, earthmovers and farming equipment, is owned by the Bamfords, one of the country’s richest families.
The company is led by Sir Anthony Bamford, one of the most outspoken supporters of Brexit.