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The thermal 1,3-dipolar cycloadditions of 4-acetoxyallenoates 1 with various dipoles have been reported. When azomethine imines and nitrones are used as the 1,3-dipole partner, the corresponding reactions afford 2,3-dihydropyrazole and 2,3-dihydroisoxazole derivatives, respectively. These reactions might proceed via a thermal 1,3-dipolar cycloaddition and the subsequent elimination of HOAc. In addition, allenoates 1 react well with in situ generated azomethine ylides in which a similar cycloaddition pathway is followed by oxidative aromatization to give indolizine derivatives.