As　the　lensless　Fourier　transform　digital　holography　is　applied　into　the　microscopic　phase-contrast　imaging　on　the　live　cells,　the　motion　of　the　cells　will　lead　to　the　non-coplanarity　phenomena　between　the　object　and　the　reference　source.　This　could　result　in　the　imaging　aberration.　An　effective　and　robust　autofocus　procedure　based　on　the　phase　distribution　is　presented　in　the　paper.　With　the　initial　measurement　of　the　distance　between　the　reference　source　and　the　hologram,　the　optimum　parameters　corresponding　to　the　phase-contrast　image　can　be　achieved　by　a　single　hologram,　combined　with　the　linearity　fitting.　The　lensless　Fourier　transform　digital　holographic　system　is　built　and　the　experiments　on　the　phase-contrast　imaging　of　the　live　cervical　carcinoma　cells　are　performed.　Finally,　the　good　experiment　results　are　demonstrated.　Both　the　theoretical　analysis　and　the　experimental　investigation　verify　the　feasibility　and　validity　of　the　automatic　procedure　for　the　non-coplanar　aberration　compensation.