This work presents a study of the thermal sensitivity of p-n short silicon diodes represented by the temperature coefficient of current (TCC) for thermal sensing applications. It proposes an analytical model (AM) of the TCC of p-n short silicon diodes under low-level injections and in the temperature range of 300–400 K. First, the TCC is studied at diffusion and recombination regimes and it is discriminated between different physical contributions. Then, it is followed by a discussion on the origins and influences of these contributions to provide a usable and simplified analytical expression of the TCC. Finally, the proposed AM is compared to technology computer-aided design (TCAD) simulations and experimental results at 300–400 K. It shows a strong correlation for different designs of p-n short diodes.