Sir, i want to know can son construct building in father's land (i.e land in name of father)with son's own capital.?

What was agreement/understanding between father and son before initiating construction of building?

Depends upon the agreed terms, even son can hold the property in his file.

Nothing such agreement has been made,the building has been in under construction  which expenses is bear by the son.Building has been shown in father's IT return.Now less capital in father File,what are the options availiable here to increase the capital in father file.

Well, if you wish the capital from son can be shown as loan or gift in father's file; but plan and act according to the future course of action.

Does the father wish to keep the building in his name? or wish to sell? etc.

NO father wish to keep in his name building.

Sir,

      Can son shows the expenses incurred in construction of building in his IT file .Though its in the land name of father.

If father wishes it to keep in his name, son has to show it as loan/gift to father. Or father and son should jointly show ownership of the building with a mutual agreement of understanding.