The company said Monday Truscott was recently involved in a serious skiing accident, and is now recovering from the incident.
"Ken Truscott was a founding director of the company, and his oil and gas expertise and insight have been invaluable as NZEC expanded from a start-up company to an oil and gas producer with operations on multiple sites," said CEO John Proust.
"On behalf of NZEC's Board of Directors and employees, I thank Ken for his valuable contributions and wish him well in his recovery."
The junior oil and gas producer said it will undertake a "comprehensive search" for a new director with oil and gas and business expertise.
Late last month, New Zealand Energy appointed Chris Ferguson as its new CFO, starting February 25.
Ferguson, who has more than 18 years of accounting and operational experience in both the public and private sectors, will be based in the company's New Plymouth, New Zealand office, and will oversee finance, accounting, administration and risk management.
The company noted he has "extensive" oil and gas experience within the Taranaki Basin, where New Zealand Energy has a significant foothold, having held senior financial positions over the past 13 years with both local and international exploration and production companies.
In January, the company provided an update on its exploration and production activities in the Taranaki Basin of New Zealand's North Island, as it prepared to spud the first well at its fourth drill site.
The company is undertaking an eight well exploration program in the Taranaki Basin, designed to increase production and cash flow. The junior oil and gas company expects to produce 3,000 barrels of oil equivalent per day once the campaign is complete - expected by the end of this quarter.
After the eight well exploration program is wrapped up, the company will then move directly into its 2013 campaign. This year's program will focus on targets that are central to the Waihapa Production Station and associated gathering pipelines, expected to expedite tie-in of discoveries and reduce transport and processing costs.
As the only open-access midstream facility in the Taranaki Basin, the station ensures the company can process its own production, as well as offers opportunities for processing third-party gas, liquids, oil and water.
The station is located around 3km from New Zealand Energy's Copper Moki site, where it already has three producing wells.