Guava (Psidium guajava L.) is a tropical fruit native to tropical America and is known as the “Apple of the tropics.” Guava cv. ‘Shweta’ is the most promising cultivar of guava grown in both tropics and subtropics because of its wide adaptability. In the northern states of the country, fruits are harvested in the months of August-September during the rainy season and in December-January during the winter season. A study was therefore undertaken to assess the effect of tree spacing on guava anatomical and reproductive behaviour. The trees were planted at six different spacings, i.e. T1 (6x5 m), T2 (5x5 m), T3 (5x4 m), T4 (5x3 m), T5 (4x4 m) and T6 (4x3 m) to estimate the yield under different spacings. This investigation revealed that characters like stomatal density and crotch angle increase with increased plant spacing, while leaf size has a reversed relation with spacing. Fruiting attributes for rainy and winter seasons viz. flower bud density (38.86 % and 14.32 %), fruit set (66.12 % and 44.67 %) and fruit retention (61.22 % and 50.22 %) were recorded higher in trees spaced at T1 (6x5 m) as compared to other spacings, whereas trees planted at closer spacing (4x3 m) has taken higher 76 days from fruit set to maturity. The number of fruits per tree, fruit yield per tree, fruiting density and yield efficiency (maximum in 5x5 m spacing) were increased with an increase in plant spacings (4x3 m to 6x5 m) while seed number per fruit was found to be decreased. Thus, the results revealed that guava planted at 5x3 m (267 trees/ acre) registered a higher yield per acre than other treatments. However, trees spaced at 5x5 m had significantly higher yields than trees planted at recommended spacing, i.e., 6x5 m.