Crystals of (2S)-2-((4-((4-((1S)-1,2-dihydroxyethyl)phenyl)ethynyl)benzoyl)(methyl)amino)-N-hydroxy-N',2-dimethylmalonamide having diffraction peaks at diffraction angles (2θ) of 3.8 ± 0.2°, 7.7 ± 0.2°, and 10.8 ± 0.2°, etc., or 8.2 ± 0.2°, 12.4 ± 0.2°, and 13.3 ± 0.2°, etc., in powder X-ray diffraction, a production method thereof, and a pharmaceutical composition.