A temporary adhesive for which temporary adhesion is simple and subsequent detachment is also simple, meaning productivity can be improved. Also, a method of producing a thin wafer that uses the temporary adhesive. The temporary adhesive composition comprises: (A) an organopolysiloxane comprising: (I) 40 to 99 mol % of siloxane units represented by R1SiO3/2 (T units), (II) 0 to 49 mol % of siloxane units represented by R2R3SiO2/2 units (D units) and (III) 1 to 25 mol % of siloxane units represented by R4R5R6SiO1/2 units (M units) (wherein each of R1 to R6 represents an unsubstituted or substituted monovalent hydrocarbon group of 1 to 10 carbon atoms), and having a weight-average molecular weight exceeding 2,000, and (B) an organic solvent having a boiling point of not more than 220° C.