Heat pipe is an effective device to dissipate heat. Due to its merits, the applications of the heat pipe is wide such as cooling of an electronic components, aerospace, biomedical, etc. The present study interested to analyse the heat pipe in various aspects as three analyses. In first analysis, the vertical gravity assisted heat pipe is analysed with various material and filling ratios. The material and filling ratio influence the performance of the heat pipe. The performance of the horizontal heat pipe with wick structure is analysed in the second analysis. The third analysis concentrates on the behaviours on the performance of the heat pipe with two different angle of bending.