Objective To investigate the application of microdissected thin anterior lateral thigh perforator flap (ALTP flap) in precise reconstruction of oral and maxillofacial soft tissue defects and to assess the clinical reconstruction outcome. Methods From January, 2014 to September, 2015, utilizing the technique of microdissected thin anterior lateral thigh flaps to repair the defects resulted from radical resections of primary sites in 42 patients with oral cancer. Before the operation, the dominant perforator was detected and marked on the skin where the planned flap would be harvested later by Doppler probing. Initial incision was made medial to the perforator marker. Careful dissection was conducted suprafascially to isolate the dominant perforator as well as identifying its source and type. The size of flap was determined according to the area of defect after tumor ablation. Meanwhile the flap was thinned in accordance with the contour of the defect or the organ to be reconstructed. The procedure should be performed under operating microscope. Results Forty-five microdissected thin ALTP flaps were harvested and used to reconstruct the defects of tongue, buccal, oral floor, and gingiva in 42 patients. Among them, 28 flaps were nourished by single perforator, 14 flaps were nourished by 2 perforators, and 3 flaps were nourished by 3 perforators. In total, 65 perforators were identified, in which 28 were direct cutaneous branches, 13 were fascia-cutaneous branches, and 24 were fascia branches. One take-back occurred within 6 hours due to cervical haematoma. During re-exploration, pedicle compression was found. And the flap was salvaged successfully after haemotoma removement and proper bleeding point ligation. Four flaps underwent marginal necrosis which healed smoothly after debridement and dressing changes. Post-operative 6 to 24 months’ follow-up showed satisfactory appearance of the recipient sites with favorable speech and swallowing function. All donor sites were closed primarily, leaving no donor-site complications including incision disruption, scar hyperplasia or muscle strength degeneration of the lower limb. Conclusion Microdissected thin anterior lateral thigh perforator flap is an optimal choice for personalized reconstruction of soft tissue defects of the tongue, buccal, oral floor, and gingiva, for it can decrease donor-site morbidity and achieve better appearance and function reconstruction effect of the recipient site. Key words: Oral and maxillofacial defects; Anteriolateral thigh flap, perforator flap; Microdissected thin flap; Microsurgical technigue