The sensitivity of shot noise to the interplay between Kondo correlations and superconductivity is investigated in a carbon nanotube quantum dot connected to superconducting electrodes. Depending on the gate voltage, the SU (2) and SU (4) Kondo unitary regimes can be clearly identified. We observe enhancement of the shot noise via the Fano factor in the superconducting state. Its divergence at low bias voltage, which is more pronounced in the SU (4) regime than in the SU (2) one, is larger than what is expected from proliferation of multiple Andreev reflections predicted by the existing theories. Our result suggests that Kondo effect is responsible for this strong enhancement.Introduction.-Kondo effect and superconductivity, two typical many-body effects, emerge in various fields of physics such as in heavy fermion systems [1], mesoscopic systems [2,3], and cold atoms [4,5]. Kondo effect arises due to formation of a spin singlet between a localized state and free conduction electrons with the characteristic energy, k B T K , where k B is the Boltzmann constant and T K is the Kondo temperature. An s-wave superconductor, for its part, is characterized by a macroscopic wave function constituted of Cooper pairs singlet with a binding energy ∆. The interplay between those two many-body states has been shown to bring new intriguing fundamental physics such as quantum transitions [6]. Superconductor-quantum dot-superconductor devices (S-QD-S) [7-12] and QD-SQUID [13-15] tuned in the Kondo regime are ideal platforms to study the interplay between the two effects.At equilibrium, a supercurrent is carried by Andreev bound states (ABS) formed in the QD. The Kondo effect manifests itself by screening the magnetic moment of the ground state and induces a first order quantum transition as observed via the current phase relation [10,[13][14][15] and spectroscopy experiments [12]. When the junction is biased with a voltage V , non-equilibrium transport occurs through multiple Andreev reflections (MAR) [7][8][9], where an injected quasiparticle at energy, eV , transfers effectively a charge me through the junction before escaping when the acquired energy, m × eV , is larger than 2∆ [16,[18][19][20].Shot noise, non-equilibrium current fluctuation, is a powerful tool to elucidate such transport mechanisms [17]. For instance, large effective charges due to the MAR mechanism depicted above have been detected in the noise measurement in S-quantum point contact (QPC)-S [21]. Regarding Kondo effect, experiments have demonstrated that the many-body effect creates a pair backscattering, which induces a large effective charge in the non-linear noise [22][23][24]. Thus, it is appealing to look