The question is unclear. I wonder what you mean by "better". Does it mean accuracy, easiness to prepare and calibrate, and/or uncertainty in model outputs?

Dear Tesfa could you make your question more clear? You are talking about small catchment with limited gauge stations? How small is your catchment?  

The answer depends on what you want to do with either of the models. If your question is to model a catchment of any size, be small in your case, SWAT has a lot catchment modelling components for  flow, sediment ...., constituent loading. 

SWAT has also calibration uncertainty packages (5) to compare your results with a range of objective functions. If you r small catchment has a sub-catchment, there is also an option to estimate ungauged catchment flow and sediment components in SWAT. 

Cheers!

Gebiaw

Tesfa

Gebiaw writes very well.

HMS is a strictly hydrological tool where the amount of water is calculated. I use it to calculate the maximum flows.

SWAT is more for water quality calculations but also for retention estimation.

If you are not interested in water quality I recommend HMS, but it is problematic for large catchments with many subbasins. I am working in a catchment area of 1500 km2 with about 120 subbasins and the model works well but but my working is a bit uncomfortable

If you want to include water quality, use SWAT.

Regards

Kris

Article COMPARISION OF THE HEC-HMS AND SWAT HYDROLOGICAL MODELS IN S...

Difference 1: SWAT can consider different land uses and soils within a subbasin, but HMS does not, which is the reason why SWAT is called spatially distributed parameter model.

Difference 2: SWAT simulates runoff, sediment, nutrient, and bacteria transports, but HMS does not.

Difference 3: HMS has the relatively less number of parameters for hydrologic simulation compared to SWAT.

Difference 4: Both models have their calibration modules, but SWAT uses SWAT-CUP that is a compilation of sampling based algorithms, and HMS uses classical optimization methods such as Newton-Rapson method.

Difference 5: I would say HMS has been used as a model for hydrologic design (in civil engineering), and SWAT has been used as a tool to assess the effectiveness of agricultural practices.

All  scholars and scientists, I have got  good insight from your recommendation.

 thank you very much 

I agree with Younggu Her, HMS usually is used as a hydrological model in order to use the results as an input to RAS for hydraulic modelling...

It's hard question to answer, because it depends on several factors...

First of all, HEC-HMS is an event based model and only simulates hourly run-off...

While SWAT model is a water balance model and only simulates daily, monthly and annually runoff not hourly based events....

From the calibration aspects, HEC-HMS usually needs a few parameters to be calibrated and needs few inputs rather than to SWAT...

In order to set up SWAT model you need several inputs such as soil map, land use map, DEM and other parameters that providing most of them in data sparse regions is relatively impossible...

but in contrast, HEC-HMS needs fewer input parameters that most of them can be easily obtained...

Finally, you should consider the objective of your simulation before selecting an appropriate model    

the best

Azizian 

Dear Meshesha

it,s depend on what is your objective and what do you want to find out.

It's also depend on your catchment characteristics,

so you can prefer a literature of your study area and Model Manual also

Can anyone tell me what is the difference between the SWAT hydrological model and the TOPMODEL model?