This study examined the effects of powder types on capillary pumping performance and wettability of wick samples. The raw material used are molecular sieve and copper powder with grain size of 80-100 microns and 177-200 microns respectively. Wick samples were produced by sintering with two shapes of powder grain comprised spherical and irregular shapes. Tests were carried out to determine the microstructure of the sample, capillary pumping amount and wettability. The test results showed that the grain type and grain size of powder could affect the roughness of the samples, of which, consequently, could also influence their wettability and capillary pumping amount. Proposed grain size and shape of the molecular sieve and copper powder are potential to be considered as wick alternatives for heat pipe application.