Context : Chromospheric evaporation is a key process in solar flares that has extensively been investigated using the spectroscopic observations .
However , direct soft X-ray ( SXR ) imaging of the process is rare , especially in remote brightenings associated with the primary flares that have recently attracted dramatic attention .

Aims : We intend to find the evidence for chromospheric evaporation and figure out the cause of the process in sympathetic coronal bright points ( CBPs ) , i.e. , remote brightenings induced by the primary CBP .

Methods : We utilise the high-cadence and high-resolution SXR observations of CBPs from the X-ray Telescope ( XRT ) aboard the Hinode spacecraft on 2009 August 23 .

Results : We discover thermal conduction front propagating from the primary CBP , i.e. , BP1 , to one of the sympathetic CBPs , i.e. , BP2 that is 60 \arcsec away from BP1 .
The apparent velocity of the thermal conduction is \sim 138 km s ^ { -1 } .
Afterwards , hot plasma flowed upwards into the loop connecting BP1 and BP2 at a speed of \sim 76 km s ^ { -1 } , a clear signature of chromospheric evaporation .
Similar upflow was also observed in the loop connecting BP1 and the other sympathetic CBP , i.e. , BP3 that is 80 \arcsec away from BP1 , though less significant than BP2 .
The apparent velocity of the upflow is \sim 47 km s ^ { -1 } .
The thermal conduction front propagating from BP1 to BP3 was not well identified except for the jet-like motion also originating from BP1 .

Conclusions : We propose that the gentle chromospheric evaporation in the sympathetic CBPs were caused by thermal conduction originating from the primary CBP .