Plasmodium knowlesi has recently been recognized as the fifth Plasmodium species causing malaria in humans. Diagnosis is difficult morphologically, and currently, available rapid tests have not been comprehensively evaluated with this pathogen. We report a case of P. knowlesi malaria that was confirmed after the initial clue of discordant microscopy and immunochromatographic results, highlighting the importance of molecular diagnostics in cases with the relevant clinical and epidemiologic history.