A new and distinct cultivar of Hydrangea plant named ‘；Hortmaspoli’；, characterized by its upright to somewhat outwardly spreading plant habit； moderately vigorous growth habit and moderate growth rate； freely branching habit with strong and thick sturdy stems； freely flowering habit； large mophead-type inflorescences with yellow green-colored sterile flowers with purple-colored centers and coarsely serrate margins； and good postproduction longevity.
