Edward Breen, a current member of DuPont's board of directors, will take the role of interim chair and CEO on that date. The board has begun the process of searching for a full-time replacement.
"Over the past seven years, with the dedication of our entire team, we have transformed this great company by focusing our portfolio, streamlining the organization and driving innovation that leverages our unique science and engineering capabilities. With a strong foundation in place, now is the right time for a new leader to continue to drive the pace of change to capitalize fully on the opportunity ahead," said Kullman.
"I want to express my sincere thanks and admiration to all of my DuPont colleagues around the world. I have complete confidence that they will realize the enormous potential of the next generation DuPont."
Kullman has been with the company for more than 27 years and became CEO in 2008.
Shares of DuPont surged 5 percent in extended-hours trade after the news.
In addition, the company lowered its 2015 EPS guidance to $2.75 from $3.10. Analysts had expected $3.19. The revised guidance was mostly due to the impact of a stronger dollar and weakness in Brazilian agriculture markets.
DuPont now expects 72 cents of negative impact per share this year from currency headwinds. The company had earlier forecast a headwind of 60 cents per share.
In a conference call on Monday, Breen told investors that the company plans a "deep dive" into the DuPont cost structure and capital allocations.
Despite the a gain of 4 percent in stock during Monday's session, shares have dropped 33 percent from their 52-week high in March.
Activist investor Nelson Peltz's Trian Fund Management is the fifth-largest shareholder in the company with 24.5 million shares, or 2.72 percent. Trian made more than $60 million from stock move.
Last spring, Peltz battled DuPont in a proxy fight over his nominating members to the board. However, in May, the company fended off the Trian Fund and was able to re-elect all 12 members of the DuPont board.