Objective The venom of carnivorous cone snails provides a valuable source of biologically active peptides, which are composed of a complex mixture of disulfide-rich neurotoxins, commonly known as conotoxin. In this work, a novel O2 superfamily conotoxin Tx7.29 was reported, and through functional research, it is expected to discover a new analgesic drug candidate.Methods The cDNA sequence of Tx7.29 was obtained from the venom duct cDNA library of the molluscivorous Conus textile collected from the South China Sea. The mature peptide Tx7.29 with modified amino acids and disulfide bonds was synthesized and identified by mass spectrometry. Patch clamp and animal experiments were used to determine the biological function of Tx7.29.Results The cDNA of Tx7.29 encodes a 68 amino acid residues conotoxin precursor, which consists of 19 residues in the signal peptide, 28 residues in the pro-region and 22 residues in the mature peptide. Circular dichroism (CD) spectra showed that β-turn and antiparallel sheet structures were dominant contents in Tx7.29. Patch clamp experiments on the rat DRG neurons showed that Tx7.29 could significantly inhibit calcium currents, but it had no obvious effects on the sodium and potassium currents. Tx7.29 increased the hot plate latency from 0.5 to 4 h in a dose dependent manner in the mice hot plate assay and had low toxicity to ND7/23 cells.Conclusion This novel conotoxin Tx7.29 may be a useful tool for analgesic drug development and could expand our visions of the molecular targets of O2-conotoxins.