A survey of weed flora of potato in north-eastern Haryana conducted during 2004-05 revealed that a total of 23 species were found to infest potato fields, out of which three were grassy, 16 broadleaf weeds and only one sedge Cyperus rotundus. C. album, A. arvensis, P .minor, Poa annua, Rumex retroflexus, Melilotus indica, Polypogon monspliensis, Coronopus didymus and Medicago denticulata were the major weeds of potato in all districts. In Panchkula and Ambala Anagallis arvensis was the most dominant weed with a relative density of 15.8, 13.6 and 19.64%, respectively, while in Kaithal and Panipat, Poa annua dominated weed flora with 48.4 and 35.7% of total weed flora followed by C.album. Malwa parviflora a robust dicotyledonous weed, which was considered to be weed of non-cropped areas, has also shown its presence in Kurukshetra and Kaithal districts. Kharif weeds Trianthema portulacastrum and Digera arvensis were found to infest early sown crop in Kurukshetra, while Portulaca oleracea was recorded in Kaithal and Panipat districts.