Accumulated intra-lesion protein such as serum albumin has been speculated to impede remineralisation of carious enamel lesions. The aim of this study was to assess whether intra-lesion bovine serum albumin (BSA) affected subsequent remineralisation of enamel subsurface lesions. Confocal microscopy was used to confirm localisation of BSA in artificial enamel subsurface lesions and its subsequent degradation by a high pH sodium hypochlorite treatment. An in vitro remineralisation experiment tested the effect of intra-lesion BSA, and its degradation by sodium hypochlorite, on remineralisation of subsurface lesions by casein phosphopeptide stabilised amorphous calcium fluoride phosphate. In addition, lesions without BSA were pre-treated with one of 2 high pH solutions (sodium hypochlorite or sodium hydroxide) prior to remineralisation to test whether the high pH pre-treatment influenced remineralisation. Data were obtained on remineralisation using transverse microradiography and were analysed with a one-way ANOVA. Intra-lesion BSA had no significant effect on remineralisation compared with that of control lesions. Pre-treatment of BSA-containing lesions with sodium hypochlorite significantly increased remineralisation. The lesions without BSA that were pre-treated with either sodium hypochlorite or sodium hydroxide also showed the same level of remineralisation as the BSA-containing lesions pre-treated with sodium hypochlorite indicating that the increased remineralisation was pH related. Hence, it was concluded that intra-lesion BSA did not affect remineralisation of artificial enamel subsurface lesions in this model system and that a high pH pre-treatment enhanced remineralisation.