Supplying proper ratios of nutrients in different stages of growth and development may increase yield and fruit quality of horticultural crops. Treatments consisted of three potassium concentrations (200, 250 and 300 mg L^-1) and two nitrogen concentrations (120 and 180 mg L^-1). To prepare the medium used 1:1 (v/v) ratio of cocopeat and perlite. In order to determine the best potassium to nitrogen ratios, some plants were continually fertigated with the same K:N ratios to the end of experiment period and other plants were fertigated with different N:K ratios in vegetative and reproductive periods. Results showed that the tenth treatment (200/180 K/N ratio in vegetative period and 300/120 ratio in reproductive period) significantly increased yield components and parameters including length, diameter, achenes number and weight of fruits, fruit set and qualitative parameters such as phenol, ascorbic acid and anthocyanin. None of the treatments had significant effect on titratable acidity, number of inflorescence and flower of the strawberry. Considering all measured parameters, the tenth treatment was the best nutrient solution. These results suggest that K:N ratio with 200/180 mg L^-1 and 300/120 mg L^-1 in vegetative and reproductive periods can be applied as a proper treatment to improve yield  and  the quality of strawberries.