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We present a photometric and spectroscopic study of AzV322, an emission lineobject located in the Small Magellanic Cloud previously classified between O9and B0. We analyze 17.5 years of $I$ and $V$ band OGLE-II, III and IV lightcurves and find four significant frequencies, viz. $f_1$= 0.386549 $\pm$0.3, $f_2$= 0.101177 $\pm$ 0.5, $f_3$= 0.487726 $\pm$ 0.000015 and$f_4$= 0.874302 $\pm$ 0.000020 c/d. The $f_1$ frequency (period 2.58700 $\pm$0.00002 days) provides the stronger periodogram peak and gives a single wavelight curve of full amplitude 0.066 mag in the $I$-band. High-resolutionoptical spectroscopy confirms the early B-type spectral type and revealsprominent double peak Balmer, Paschen, OI 8446 and HeI 5875 emissions. Thespectral energy distribution shows significant color excess towards longwavelengths possibly attributed to free-free emission in a disk-like envelope.Our analysis yields $T_{eff}$ = 23000 $\pm$ 1500 K, log g = 3.0 $\pm$ 0.5, $M$= 16 $\pm$ 1 M$_{\odot}$, $R$ = 31.0 $\pm$ 1.1 R$_{\odot}$, and $L_{bol}$ =10$^{4.87 \pm 0.06}$ $L_{\odot}$. AzV322 might be a member of the new class ofslowly pulsating B supergiants introduced by Saio et al. (2006) and documentedby Lefever, Puls & Aerts (2007), however its circumstellar disk make it anhitherto unique object. Furthermore, we notice that a O-C analysis for $f_1$reveals quasi-cyclic changes for the times of maximum in a time scale of 20years which might indicate a light-travel time effect in a very wide orbitbinary with an undetected stellar component.

The SMC B-type supergiant AzV322: a g-mode pulsator with a circumstellar disc