The invention relates to a method and equipment for controlling flatness of a stainless steel strip in connection with cooling after annealing in a finishing line. The strip (1) is first in the direction of the strip movement (2) cooled feeding at least one cooling medium through at least one group of feeding devices (5, 6) located transversally to the direction of the strip movement for the whole width of the strip (1), the amount of the cooling medium being adjusted utilizing the recorded and predetermined data (7) of desired temperature of the strip for flatness, the temperature of the strip is then determined (8) and after the temperature determination a further step of cooling is carried out feeding at least one cooling medium through at least one group of feeding devices (9) located transversally to the direction of the strip movement (2), when the determined value of temperature is different from the predetermined value of temperature, before the flatness is controlled using a control device (11) containing a plurality of flatness control units (12) and locating transversally to the direction of the strip movement (2).