This study examines the architectural motifs of St. Augustine Church (Paoay Church) and their cultural and historical significance within the Ilocano context. Employing a qualitative ethnographic design and guided by Charles Sanders Peirce’s semiotic framework, the research analyzed motifs as visual signs that convey layered meanings. Data were gathered through in-depth interviews, participant observation, and thematic analysis involving heritage experts, cultural workers, and local community members. Findings revealed that motifs such as the Royal Coat of Arms, Augustinian emblems, rosettes, shells, celestial symbols, and foliate patterns function as symbolic representations of colonial authority, religious belief, environmental adaptation, and indigenous artistic expression. These elements demonstrate a synthesis of European and local influences, reflecting the values, identity, and lived experiences of the Paoayeños. The study concludes that Paoay Church serves not only as a heritage structure but as a living cultural narrative sustaining community identity and artistic continuity.