The present invention provides a fluid state detection sensor accurately detecting a fluid state by suppressing the deterioration of a
conductivity measurement accuracy due to its characteristics. The sensor comprises an
electrode section configured by a pair of electrodes arranged opposite each other, a
conductivity acquisition unit detecting a resistance value from an inter-
electrode voltage value acquired through the
electrode section and acquiring a fluid
conductivity, a controller executing entire sensor's
processing according to a control program stored in ROM etc., a memory storing correction values for fluid whose conductivity is greater than a predetermined value calculated by a conductivity
calculator, which calculates the fluid conductivity from the inter-electrode
voltage value, a corrector correcting the conductivity
calculator calculated conductivity using the correction value stored in the memory when the fluid whose conductivity
calculator calculated conductivity is greater than the predetermined value, and an output section outputting corrected conductivity.