The vice president for external affairs of Harvard Management Company (HMC), which manages the University’s $18.3 billion endowment, will leave HMC after 14 years to serve as Wellesley College’s first chief investment officer.

When she assumes her new position on Feb. 1, Jane Mendillo will work with a significantly smaller endowment of approximately $1 billion.

She said the career move will give her more direct influence as an investment manager.

Mendillo said she sees her new position as a change from “a secondary [one], choosing and monitoring external managers” at HMC to “managing an entire portfolio, choosing managers and communicating with Wellesley’s investment committee.”

HMC has not yet hired a replacement, according to Mendillo.

The president of HMC could not be reached for comment yesterday.

Mendillo said she expects to remain in the new position for at least five years.

Wellesley’s investment committee has managed the college’s endowment in the past. But because of its increasing endowment, Wellesley has decided to create a daily management team and shift the investment committee’s role to an “advisory” one, Mendillo said.

“I will have the opportunity to set something up and have an impact on their organization at a pretty broad level,”said Mendillo, who has managed approximately $7 billion in assets during her time at HMC.

Prior to assuming her current position in 1998, Mendillo served as HMC’s vice president for private equity and vice president for trusts.

“Jane Mendillo has an outstanding record of choosing and managing an investment team,” said Wellesley President Diana Chapman Walsh in an official announcement of Mendillo’s appointment.

“The search committee [was] impressed by her thoughtful leadership, her fund management skills and her enthusiasm and energy.”

Susan Vogt, treasurer and vice president of finance at Wellesley, said that Mendillo’s new job will put her “in charge of all endowment assets.”

Vogt and members of Wellesley’s investment committee made up the search firm that selected Mendillo.

“We hope she’ll bring leadership for our growing investment office, a significant expertise in managing investment activity and contacts and connections in the investment of endowments,” Vogt said.