In this paper, the effect of sun protection agent on different hair samples including, (i) unbleached hair sample, (ii) bleached hair sample and (iii) bleached hair sample with subsequent hair coloration, were studied. This paper was aimed at evaluating the effectiveness of sun protection agent on the different hair conditions. The hair samples were divided into two sets; one was the samples applied with sun protection agent, while the other one was without the application of sun protection agent. The results of colour change were evaluated by means of CIE $L^*a^*b^*$ values of samples and the tensile strength of hair was measured using tensile testing machine. In the case of colour change, the overall results showed that there was a decrease in colour change when the sunlight exposure time was prolonged. At the same time, the hair samples treated with the sun protection agent could provide a lower change in colour than the hair samples without the sun protection agent. With respect to the tensile strength properties, the results obtained indicated that the breaking load of treated samples decreased when the sunlight exposure time was prolonged. The change in tensile strength of the samples treated with the sun protection agent was smaller than the hair samples without the sun protection agent. In addition, the results indicated that the coloration process did not further decrease the tensile strength of hair samples.