Abstract The thermoelectric transport properties of Fe- and Ti-adsorbed blue phosphorene nanoribbons are studied using the first principles approach. The research indicates that Fe- and Ti-adsorbed blue phosphorene nanoribbons exhibit spin-dependent Seebeck effect. The devices based on the Fe-adsorbed blue phosphorene nanoribbons show perfect spin filtering effect caused by 100% spin polarization and 106% tunnel magnetoresistance. The spin-up current and the spin-down current are reversed in Ti-adsorbed blue phosphorene nanoribbons, indicating that a large spin current and a small charge current can be generated. These systems also exhibit negative differential resistance induced by the current-voltage curve. The band structures and transport spectrums are utilized to explain the physical mechanism of spin current generation. Metals-adsorbed blue phosphorene nanoribbons can be considered novel thermoelectric materials and used to make multifunctional thermal spintronic devices.