The layoffs are the major portion of a US$400 million cost-cutting plan Yahoo is implementing that also includes other measures for achieving what the company called "structural efficiencies."
Revenue for the third quarter, which ended Sept. 30, increased only 1 percent to $1.768 billion compared with the same quarter in 2007.
Subtracting the commissions Yahoo pays to its advertising partners, revenue was $1.325 billion, up 3 percent.
Net income came in at $54 million, or $0.04 per share, down from net income of $151 million, or $0.11, in 2007's third quarter.
On a pro forma basis, which takes into account one-time items, net income was $123 million, or $0.09 per share, down from net income of $153 million, or $0.11 per share.