A solid acid catalyst (SACR) was prepared from waste catalyst of heavy oil catalytic cracking via acid impregnation, and applied to catalyze the esterification of turpentine with anhydrous oxalic acid. Gas chromatography-mass spectrometry (GC-MS) was employed to investigate main and side reaction pathways. Response surface methodology (RSM) was used to optimize the esterification process and synthetic borneol was ultimately synthesized via saponification. The results indicated that the catalytic esterification of turpentine proceeds follow a carbocation mechanism, with the predominant reaction involving the protonation of α-pinene followed by esterification with oxalic acid, accompanied by concurrent side reactions such as isomerization-esterification, isomerization, and dehydrogenation; the main products were bornyl esters, including dibornyl oxalate, bornyl fenchyl oxalate, bornyl isobornyl oxalate and bornyl formate. The isomeric byproducts mainly included monoterpenes. The optimal esterification conditions were determined to be a reaction temperature of 97.5 ℃, a reaction time of 5.2 h, and n (oxalic acid): n (α-pinene) =0.51, under which the α-pinene conversion rate reached 99.54%, and the yield of oxalate-bornyl ester was 48.41%. After saponification, the synthesized borneol contained 85.22% borneol, meeting the standards of the Chinese Pharmacopoeia.