Friday's home defeat by Cardiff means Blackpool have won just one of their past eight Championship matches, losing their past threeManager Mick McCarthy has left Championship strugglers Blackpool after less than three months in charge.
A 3-1 home defeat by Cardiff on Friday left Blackpool second bottom of the table, seven points from safety.
McCarthy said: "I have thought long and hard and feel this is the best decision for everyone concerned with the football club."
Assistant manager Terry Connor has also left, and development coach Stephen Dobbie will take charge until the end of the season.
After succeeding Michael Appleton, McCarthy had to wait six games for his first win, a 1-0 home victory over Stoke in mid-February.
Blackpool won only one of their next eight games - a 6-1 thrashing of QPR, with Friday's loss against Cardiff their third successive defeat.
A club statement read: "With results on the pitch not improving in recent weeks, the decision has been agreed by both parties that a change is needed."
Blackpool travel to play-off contenders Luton on Monday.
