Multiple biochemical parameters showed significant differences between mild COVID-19 patients and HC, including increased concentrations of CRP (median (IQR) 1.9 (1.1–5.5) vs. 1.1 (0.7–1.4) mg/L, p = 0.041) and decreased concentrations of WBC (4.3 (3.6–5.9) vs. 5.6 (4.8–7.1) × 109/L, p = 0.001) and albumin (44.0 ± 3.2 vs. 45.7 ± 2.2 g/L, p = 0.020) in patients with mild COVID-19. Here, CRP is linked to COVID-19.