Laboratory experiment was conducted to test the effects of bio-medicinal plants (Gongronema latifolium (Utazi) leaves and Myristica fragans (Nutmeg) seeds) and synthetic fungicide (Alpron- Plus) on seed health, germination percentage and seedling vigour of sweet melon seeds. The experiment was conducted at the Crop Science and Horticulture Laboratory, Nnamdi Azikiwe University Awka, Anambra State. Bio-medicinal plants were used as crude powdery seed dressers as well as synthetic fungicide. The experiment was laid out in a simple completely randomized design (CRD) with ten replications which consisted of blotter paper germination/ seed health tests of sweet melon seeds and seedling vigour and seedling vigour index tests using soil medium. Ten petri dishes and ten polybags were used respectively for each of the plant extracts and synthetic fungicides simultaneously for both blotter paper and soil medium tests. Twenty seeds which were independently dressed with various plant extracts and synthetic fungicide were plated into one 9cm Petri dish containing three layers of blotter paper in circular form. For soil medium method, ten polybags with few small perforations underneath filled with sterilized top soil were used for each fungicide. The Petri dishes containing the plated seeds were incubated on the Laboratory benches for eight days while seedlings in polybags were kept in the screenhouse and observations were taken and recorded daily for germination count, fungal growth then germination index and seedling vigour index which were derived later with appropriate formulae and their values being expressed in percentages. The results of this investigation revealed that bio-medicinal plant crude extracts had significant effect on germination percentage and germination index of Sweet- melon seeds. Gongronema latifolium crude extract had the highest germination index. The synthetic fungicide was effective in protecting the seeds of sweet melon though had low germination percentage. Nutmeg was not effective when used in crude powdery form as dressers as it had the lowest germination percentage and the highest infestation percentage. It could therefore be recommended that the plant extracts tested in this experiment should not be used as powdery seed dressers but as essential oil using appropriate extracting solvents in order for the bioactive ingredients to act effectively in preventing micro-organisms that hinder germination of sweet melon seeds.