To provide a fluid detecting sensor capable of constituting a highly accurate and highly responsive airflow sensor.

A linking member 16 is provided to link a heater 10 and downstream-side and upstream-side temperature measuring resistors 8 and 9 arranged at equal intervals with respect to the heater 10 so as to enable thermal conduction between them. The linking member 16 is normally formed of the same material as that of the temperature measuring resistors 8 and 9 or that of the heater 10. In addition, the linking member 16 is formed of a member in the shape of a narrow line similarly to the temperature measuring resistors 8 and 9 or the heater 10. In this case, the linking member 16 is connected so that a boundary layer formed on the surface of the linking member 16 by air flowing in a perpendicular direction with respect to the temperature measuring resistors 8 and 9 may become thin.