The hottest lottery ticket in Illinois may be for a chance at a playoff seat for the Chicago Cubs.

The National League club announced yesterday that tickets for the playoffs and the World Series would be made available to the public through a lottery, similar to the multimillion-dollar state lottery.

Nearly 7,000 tickets per game will be available to the public. Each winner will be billed for two tickets for one playoff or World Series game, with the game chosen by the Cubs.

To enter the lottery, a postcard must be mailed to the team at P.O. Box 6805, Chicago, Ill., and be postmarked between Sept. 17 and Sept. 20 . . .

Meanwhile, two Cubs fans used to watching baseball from a rooftop across the street from Wrigley Field are suing their landlord because he wants them off the roof during the playoffs.

Tenants John A. Duncan and James W. Eakle said in their suit that owner Steven D. Woodruff either plans to rent or has rented the roof of their apartment for $5,000 to an unnamed business so its employes can watch the playoff games . . .

Kansas City fans can purchase two tickets to an American League Championship Series game and/or a World Series game should the Royals win the AL Western Division, the club announced.

Ticket requests must have a Sept. 17 postmark to qualify for a random drawing.

Tickets for a championship series game cost $15 each for reserved seating and $8 for standing room only. Tickets for a World Series game are $25 for reserved seating and $15 for standing room only. There is a $3 handling charge for each request filled.

Tickets requests for a championship series game should be mailed to Championship Baseball, P.O. Box 1000, Kansas City, Mo., 64141. For a World Series game, the request should be mailed to Championship Baseball, P.O. Box 1970, Kansas City, Mo., 64141.