Provided are a semiconductor device and a semiconductor system, which can increase immunity against noises through tertiary correlated double sampling (CDS). The semiconductor device includes an amplifier that receives noise and a driving signal, resets for each predetermined period of the driving signal and samples the noise to generate first sampled noise. The first sampled noise includes multiple noise differences each occurring between consecutive reset points. A sampler performs second sampling and third sampling on the first sampled noise and performs fourth sampling on the second and third sampled noises. The first sampled noise includes first to third noise differences, the second sampled noise is a difference between the first and second noise differences, the third sampled noise is a difference between the second and third noise differences, and the fourth sampled noise is a difference between the second and third sampled noises.