PURPOSE: To provide a recording and reproducing device of a reel drive system executing recording and reproducing with the constant tape traveling, and also, provide a fine servo executed at intervals of a short time.

CONSTITUTION: The output of a tape traveling speed detecting means 12 is detected by a measurement 21 every 1/(n) rotation, and simultaneously, values measured (n) times in past are held by a 36, then the rotational period T is obtained from the values measured (n) times in past by an addition 37. Then, a deviation (d) to the preccribed traveling speed of the tape is calculated by a calculation 22 from the T being traveling speed information and a servo control value L is calculated by a calculation 25 by using the deviation (d).