The resist thickness of EUV lithography is thin less than 50 nm. Since the most photon is not absorbed by the resist, the EUV chemical reaction is not occurred sufficiently. In order to increase chemical reaction, a resist should have a highabsorption material compounds for the EUV photons. Many high-absorbing material has been studied such as hafnium, zinc, tin oxide, and tellurium. Resist performance improvements are expected in sensitivity and reduction of line-edgeroughness. For the development of the high-absorbing resist materials, it is significant to measure the EUV absorption coefficient accurately. For measurement of absorption, it is necessary to measure both transmittance and thickness of resist accurately. We have developed an absorption-coefficient-measurement method of the EUV resist at BL-10 beamline of NewSUBARU synchrotron light facility. The resist is coated on a detector photodiode directly, and EUV transmittance and thickness are measured. We measured an absorption coefficient of PMMA resist, which has very simple chemical composition and ZEP520A resist which is copolymer. The transmittance uniformity on the photodiode was less than 0.6%. This result indicates that the resist sample was coated with good uniformity on the surface of the photodiode. The result of PMMA well corresponded to the calculated value. Thus, it is practicable to measure the absorption coefficient accurately.