The　fast　development　of　supercapacitors　inspires　a　growing　interest　in　inexpensive　super-capacitive　electrode　material　with　high　performance.　Herein,　we　develop　a　Rone　step　method　for　preparing　Cu3P　nanocrystals　by　direct　low-temperature　phosphorization　treatment　of　commercial　copper　powder.　As　a　super-capacitive　electrode　material,　for　the　first　time,　Cu3P　nanocrystals　exhibit　outstanding　electrochemical　rate　performance　(318.5　F　g(-1)　at　400　mV　s(-1);　169.2　F　g(-1)　at　50　A　g(-1))　and　excellent　cycling　stability　with　no　loss　of　specific　capacitance　at　10　A　g(-1)　for　10,000　cycles.　The　presented　synthesis　method　opens　up　a　facile　and　large-scale　approach　to　explore　high-performance　and　low-cost　Cu3P　electrodes　for　supercapacitors.