N-(4-Tetrahydropyranyl-oxy-phenyl)maleimide (THPMI) was prepared and polymerized by radical or anionic initiators. THPMI could be polymerized by 2,2＇-azobis(isobutyronitrile) (NBN) and potassium tert-butoxide. Radical polymers (poly(THPMI)r) were obtained in 15-50% yields for AIBN in THF at 65 degrees C after 2-5 h. The yield of anionic polymers (poly(THPMI)a) obtained from potassium tert-butoxide in THF at 0 degrees C after 20 h was 91%. The molecular weights of poly(THPMI)r and poly(THPMI)a were M-n = 2750-3300 (M-w/M-n = 1.2-3.3) and M-n = 11300 (M-w/M-n = 6.0), respectively. The difference in molecular weights of the polymers was due to the differences in the termination mechanism of polymerization and the solubility of these polymers in THF. The thermal decomposition temperatures were 205 and 365 degrees C. The first decomposition step was based on elimination of the tetrahydropyranyl group from the poly(THPMI). Positive image patterns were obtained by chemical amplification of positive photoresist composed of poly(THPMI) and 4-morpholinophenyl diazonium trifluoromethanesulfonate used as an acid generator.