The improved plumbing P-trap is a plumbing fixture. The improved plumbing P-trap attaches the drain of a sink to a DWV. The improved plumbing P-trap transports gray water into the DWV from the sink. The improved plumbing P-trap comprises a modified P-trap, a second clean out plug, and a snake guide. The modified P-trap transports gray water from the sink drain to the DWV. The second clean out plug is the modification to the modified P-trap that provides access to the DWV side of the modified P-trap. The second clean out plug is intended for use with a plumbing snake. The snake guide: 1) opens the second clean out plug; and, 2) attaches to the second clean out plug to guide the plumbing snake into the DWV.