fluid evaluation device (1) is a laser beam to the measurement object (100) in which fluid is flowing inside the irradiation means for irradiating (LB) (11), the laser irradiated onto the object to be measured a light capable of receiving means of light (12), from the first light receiving signal based on the signal strength of the received light signal receiving means has received, a first calculating means for calculating the concentration (N) of the fluid (146), (i ) from the concentration of the second light receiving signal and (ii) first calculating means based on the frequency change of the received signal is calculated due to the Doppler shift of the laser beam irradiated to the object to be measured, the fluid flow (Q) and fluid and a flow velocity (v) at least one second calculating means for calculating a (143).流体評価装置(1)は、内部に流体が流れている被測定対象(100)に対してレーザ光(LB)を照射する照射手段(11)と、被測定対象に照射されたレーザ光を受光可能な受光手段(12)と、受光手段が受光した受光信号の信号強度に基づく第1受光信号から、流体の濃度(N)を算出する第1算出手段(146)と、(i)被測定対象に照射されたレーザ光のドップラシフトに起因する受光信号の周波数変化に基づく第2受光信号及び(ii)第1算出手段が算出した濃度から、流体の流量(Q)及び流体の流速(v)の少なくとも一方を算出する第2算出手段(143)とを備える。
