Usage of traditional, complementary and alternative medicine (TCAM) has gained popularity over the pastfew years. However, very little is known about TCAM use among Malaysian cancer patients. This study aimedto identify the determinants of TCAM usage among cancer patients with determination of relationships betweendemographic factors, patient satisfaction with conventional treatment, knowledge on TCAM and healthcareprofessional influence. Patient’s perceptions towards TCAM were also determined. A simple random convenientsampling method was used to recruit 354 patients from Hospital Kuala Lumpur between February to April2013. All were directly interviewed with a structured questionnaire. In this study, 172 respondents were TCAMusers. There was no significant differences between demographic background of respondents in the usage ofTCAM. Minimal correlation was found between patient satisfaction with the conventional treatment and usageof TCAM (r=0.091). A poor correlation was found between healthcare professional’s influence and TCAM usage(r=-0.213) but the results suggested that increase in influence would decrease TCAM usage. Patient TCAMknowledge correlated negatively with the TCAM usage (r=-0.555) indicated that cancer patients are less likelyto use TCAM when they have more TCAM knowledge. Healthcare professionals should be fully equipped withthe necessary TCAM knowledge while maintaining patient satisfaction with the conventional treatment. Theyshould also intervene on patient TCAM usage where a potential drug interaction or a harmful adverse eventcan occur.