Photodynamic therapy (PDT) with methyl aminolevulinate (MAL) is approved in Europe for the treatment of actinic keratosis and Bowen's disease, both intraepithelial forms of squamous cell carcinoma (SCC). A therapeutic effect of MAL--PDT has been recently suggested for superficial, microinvasive and well--differentiated cutaneous SCC. We describe the successful use of MAL--PDT in a recently observed patient with microinvasive SCC of the lower lip and review published data on the use of PDT with MAL or --aminolevulinic acid (ALA) in cutaneous microinvasive SCC. A patient with a biopsy--proven recurrent microinvasive SCC of the lower lip was treated with 2 cycles of MAL--PDT. Complete clinical, dermoscopic and histopathological clearance was obtained after 2 cycles of MAL--PDT with an excellent cosmetic result and a sustained remission after 24--month follow--up. A review of the few studies reporting on the use of MAL--PDT or ALA--PDT for cutaneous microinvasive SCCs was carried out. MAL--PDT might represent a non--invasive treatment option for microinvasive SCC of the lower lip if patients are not eligible for surgery. Post--treatment histopathological confirmation and a long--term follow--up are strictly recommended.