The ultrasound observation apparatus according to the present invention is provided with: a feature quantity calculating unit that calculates respective feature quantities of a plurality of frequency spectra obtained by analyzing the frequency of ultrasound signals an attenuation rate setting unit which calculates a preliminary correction feature quantity of each frequency spectrum for each candidate attenuation rate value by performing an attenuation correction on the feature quantity of each frequency spectrum to eliminate the influence of ultrasound using the candidate attenuation rate values for a plurality of unit lengths and unit frequencies that impart attenuation characteristics different from each other in divisional areas obtained by dividing an ultrasound image into a plurality of areas, and which sets an optimized attenuation rate for an object to be observed among the plurality of candidate attenuation rate values and a feature quantity correcting unit which calculates an accumulated attenuation rate per unit frequency at a sampling point using the optimized attenuation rate of the divisional area present between the surface of an ultrasound oscillator and the sampling point, and which performs attenuation correction on the feature quantity using the accumulated attenuation rate to calculate the correction feature quantity.La présente invention concerne un appareil dobservation à ultrasons équipé: dune unité de calcul de quantité de caractéristiques qui calcule des quantités de caractéristiques respectives dune pluralité de spectres de fréquences obtenus en analysant la fréquence de signaux ultrasonores dune unité de réglage de taux datténuation qui calcule une quantité de caractéristiques de correction préliminaire de chaque spectre de fréquence pour chaque valeur de taux datténuation candidate par la réalisation dune correction datténuation sur la quantité de caractéristiques de chaque spectre de fréquence pour éliminer linfluence dultrasons au moyen
