In overweight patients with T2D, HOMA-β was positively correlated with the levels of amino acids including Asp, Cys, Hcy, Pro, Val, and Pip (A–F) and negatively correlated with Ser (G), and it was negatively with the level of acylcarnitine C14DC (H). ** The correlation was significant at a confidence level of 0.01; * the correlation was significant at a confidence level of 0.05; R: Spearman’s rank correlation coefficient.