The New York Times Co. reported a 43 percent jump in first-quarter profits today, mainly because of a sharp earnings increase at its key subsidiary, the New York Times newspaper.

Arthur Ochs Sulzberger, chairman of the company, told shareholders that the newspaper's profits climbed 77 percent -- from $5.3 million in the first quarter of 1979 to $9.4 million this year -- because of a 14 percent increase in advertising linage and a circulation increase of 51,000 papers a day.

The company as a whole -- which also publishes magazines, regional newspapers and books and owns television stations and paper mills -- reported record first-quarter earnings of $10.9 million (90 cents a share) on revenues of $170.4 million. During the first three months of 1979, the company earned $7.6 million (64 cents) on revenues of $145 million.

In the first quarter of 1979, the New York Times still was recuperating from an 88-day strike that ended in November 1978 although the newspaper profits and revenues in the first quarter of 1979 were above those recorded in the first three months of 1978.

Sulzberger told shareholders meeting at Carnegie Hall that its magazine division had reduced profits because of start-up costs involved with a TV guide in Australia.

Sulzberger, in response to a question, said that the newspaper's plan to begin publishing an edition in Chicago to serve its Midwest readers is the beginning of an attempt to publish a national newspaper.

Sulzberger said the decision to begin printing in Chicago was triggered by the sharp cost increase in moving newspapers by air (up 60 percent over 1979) and the difficulty in delivering the paper because of changing flight schedules. The new edition -- which will be in two sections rather than the Times' normal four daily sections -- will serve Chicago's 11,000 daily Times readers and 40,000 Sunday readers as well as readers in a nine-state area surrounding Illinois.

Sulzberger said he hoped that Cyrus Vance, who resigned as Secretary of State Monday, would return to the Times' board of directors. But Vance received only 30 votes for a position on the board after he was nominated by a stockholder.

Sulzberger said the record first quarter follows the best year the Times ever had and attributed the companys financial success to a management restructuring last summer.

Six months after the restructing, long-time executive James Goodale resigned to return to private law practice, apparently because he wasn't named president of the company, a title that went to Walter E. Mattson. The Times will pay Goodale $169,125 in salary for the rest of 1980 and another $750,000 over three years starting next January.