An encapsulation composition for pressure signal transmission including a flexible and low modulus epoxy resin as a substance in combination with plastic balls with pressure signal transmission properties as filler is provided. Therefore, the pressure signal is transmitted by utilizing the property of easy deformation of the flexible epoxy resin under pressure. And the effect of signal transmission is enhanced by the contact between plastic balls. The encapsulation composition is used in a sensor for transmitting pressure signals. The encapsulation composition is hydrophobic, so an electronic device of the sensor can be protected against moisture or water to extend its lifetime. Compared with traditional sensors using liquid for transmitting pressure signal, this sensor using solid encapsulation composition has advantages such as easy production and processing.