McKinney, 58, whowith Compaq's chief financial officer, Jeff Clarke, has been the lone head of the integration effort since Clarke late last year. McKinney had also been .
In an e-mail to employees, HP CEO Carly Fiorina praised McKinney, who began his career in 1969 as a sales engineer in HP's Santa Clara, Calif., office.
"Today, the largest technology merger in history is widely considered to be a model for integration excellence, and Webb's leadership was important to this success," Fiorina said.
Prior to HP's merger with Compaq, McKinney served as president of HP's Business Customer Organization. McKinney had also served as general manager of a variety of HP units, including its PC Software Division, Home Products Division and its overall Personal Computing Organization.
McKinney's retirement comes as a number of other HP executives have left the company. On Tuesday, HP said that former server executive, while a handful of storage executives have gone to rival EMC.
HP said it plans to reassign the various units McKinney had been overseeing. The Strategic Change office, headed by Barbara Braun, and its strategy for emerging countries, headed by Richard Walker, will now report to Chief Technology Officer Shane Robison. Meanwhile, HP's Corporate Affairs, headed by Debra Dunn, will now report to Chief Marketing Officer Mike Winkler.