A novel design of multichannel biosensor based on surface plasmon resonance photonic crystal fiber is proposed and analysed using full vectorial finite element method. The analyte detection can be performed using four modes, $${\text{H}}_{11}^{\text{x}}$$ , $${\text{H}}_{11}^{\text{y}}$$ , $${\text{H}}_{12}^{\text{x}}$$ , and $${\text{H}}_{12}^{\text{y}}$$ , which offers the possibility of multi-channel/multi-analyte sensing with high accuracy. The sensor geometrical parameters are studied to achieve high sensitivity for the four studied modes. The reported sensor has relatively high sensitivities up to 2200, 2400, 2200, and 2400 nm/RIU according to the $${\text{H}}_{11}^{\text{x}}$$ , $${\text{H}}_{11}^{\text{y}}$$ , $${\text{H}}_{12}^{\text{x}}$$ , and $${\text{H}}_{12}^{\text{y}}$$ modes, respectively. Additionally, the structure of the suggested sensor is easy for fabrication with standard PCF fabrication technologies.