The aim of this preliminary study was to investigate the influence of low level laser therapy (LLLT) in alleviating pain caused by micro-marsupialization and the healing of oral ranulas and selected mucoceles. Eleven patients underwent micro-marsupialization treatment associated with LLLT. The patients were irradiated with a 660-nm continuous wave from an indium-gallium-arsenide-phosphorous (InGaAsP) diode laser, at 100 mW, with a spot size on the tissue surface of 0.0283 cm(2) (irradiance = 3.53 W/cm(2)). Irradiation was carried out immediately following micro-marsupialization treatment, as well as at 24, 48, and 72 h post-micro-marsupialization. All treated oral ranulas and selected mucoceles presented clinical healing. No evidence of recurrence could be identified during a mean of 11.0-month follow-up period. The use of InGaAsP diode lasers, within the parameters tested, appears to present a good alternative treatment to reduce pain and heal oral ranulas and selected mucoceles associated with micro-marsupialization.