Scientific inquiry skills are crucial for scientific literacy and cognitive development in the 21st century. Prior research has identified key inquiry skills-- data analytics (DA), control of variables (COV), and scientific reasoning (SR)--but has not validated these skills through comprehensive assessments. The aim of this study was to validate and examine the relationship between students' inquiry skill profiles and their scientific competency. Through latent profile analysis (LPA), this study classified 667 Taiwanese high school students into three profiles: Sophisticated, Experimental, and Basic. The Sophisticated profile demonstrated strong proficiency in DA, COV, and SR, while the Experimental profile excelled in DA with moderate COV and SR skills. The Basic profile revealed deficiencies across all inquiry skills. ANOVA results indicated significant differences in scientific competency across profiles, with Sophisticated students outperforming others. Additionally, students' majors significantly influenced profile distribution, with natural science majors more likely to be classified as Sophisticated or Experimental. No significant relationship was identified between inquiry profiles and gender, parental education, or financial status. These findings highlight the importance of reasoning skills in scientific competency and suggest the need for tailored educational interventions to enhance students' inquiry abilities. The study provides empirical evidence for the applicability of inquiry skill profiles in diverse educational contexts.