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We report on the XMM-Newton observation of HP Cet and Swift J0820.6-2805, twoX-ray photon sources that are candidates to be members of the intermediatepolar class of cataclysmic variables. If the historical optical light curve ofHP Cet shows a periodic feature at $\simeq 96$ minutes, a clear identificationof such a signature in the high energy band (apart for a variability on a timescale of $\simeq 8$ minutes as detected by the ROSAT satellite) is lacking. Byusing XMM-Newton archive data, we clearly identify a feature (at $\simeq 88$minutes) which is marginally consistent with one of the binary system orbitalperiods reported in the literature. We also found a signature of a periodicfeatures on the time scale of $\simeq 5.6$ minutes. In the case of SwiftJ0820.6-2805, the intermediate polar nature was previously unclear and theorbital and the white dwarf spin periods were unknown. Here, the 0.3-10 keVdata undoubtedly reveal an orbital period and a white dwarf spin of $\simeq87.5$ minutes and $\simeq 27.9$ minutes, respectively. The spectral analysisshowed that both HP Cet and Swift J0820.6-280 are members of the under-luminousIP subclass since their luminosity in the $0.3-10$ keV band is estimated to be$\simeq 5\times 10^{30}$ erg s$^{-1}$ and $\simeq 3.8\times 10^{29}$ ergs$^{-1}$, respectively.

HP Cet and Swift J0820.6-2805: two candidate intermediate polars observed by XMM-Newton